Kanjimori - Glossary

Character Types

Pictograph 象形文字

A character or symbol that shows the appearance of an object. Though many kanji characters began as pictographs, heavy stylization has made them unrecognizable when compared to the objects they originally depicted. For this reason, kanji characters are generally considered logographs, not pictographs.

Examples:

The emoji 🌳 is a pictograph of a tree
The Egyptian hieroglyph 𓅓 is originally a pictograph of an owl but was later used phonetically for the sound "m"

Ideograph 表意文字

A symbol that visually represents a concept or idea and is typically not language-specific.

Examples:

The emoji ❤️ represents the idea of love across many languages
The symbol ∞ represents the idea of infinity across many languages
The symbol ♀ represents the idea of female across many languages

Logograph 表語文字

A symbol that means a word within the context of a specific language. Kanji characters are generally considered logographic.

Examples:

The kanji 山 ("mountain") was originally a pictograph of a mountain but was later stylized to be unrecognizable outside of languages written with Chinese characters
The Egyptian hieroglyph 𓇳 is a pictograph of the sun and can function as a logograph for the word "rꜥ" ("sun" or the sun god Ra) in Ancient Egyptian
The Sumerian cuneiform sign 𒀭 was originally a pictograph of a star and can function as a logograph for the words "an" ("sky") and "dingir" ("god")

Kana 仮名

Phonetic characters derived from kanji that represent sounds in Japanese. This includes characters from the two standardized kana systems (hiragana and katakana) as well as non-standard characters (hentaigana) and historical kana.

Examples:

か is a kana, specifically a hiragana character
カ is a kana, specifically a katakana character
𛀁 is a kana, specifically a hentaigana corresponding to the hiragana character え derived from the kanji 江
ゐ is a kana, specifically a historical kana used to represent "wi", a sound that later merged with "i" in modern Japanese

Kanji 漢字

Characters of Chinese origin used to represent meaning in Japanese. Kanji can be used to write whole words or parts of words, often in combination with okurigana.

Examples:

山 is a kanji that means "mountain"
毎日 is a kanji compound that means "every day"
作る is a kanji with okurigana that means "to make"

Kana Types

Hiragana 平仮名

Hiragana are a set of kana used to write Japanese phonetically. They are primarily used for native Japanese words (wago) and grammatical elements, and can appear alone or alongside kanji as okurigana. In contrast, katakana are mainly used for foreign loanwords (gairaigo), scientific names, and emphasis. Hiragana are historically derived from cursive forms of Manyōgana characters.

Examples:

あ is a hiragana character representing the sound /a/
きゃ is a hiragana combination representing the sound /kya/
ば is a hiragana character with dakuten representing the sound /ba/
ぱ is a hiragana character with handakuten representing the sound /pa/
むっつ is written in hiragana and includes a sokuon mark (small っ) to indicate a brief pause (geminated consonant)

Katakana 片仮名

Katakana are a set of kana used to write Japanese phonetically. They are primarily used for foreign loanwords (gairaigo), scientific names, and emphasis. In contrast, hiragana are mainly used for native Japanese words (wago) and grammatical elements. Before World War II, katakana was more widely used in formal writing and often served roles now associated with hiragana. Katakana are historically derived from parts of Manyōgana characters.

Examples:

ア is a katakana character representing the sound /a/
キャ is a katakana combination representing the sound /kya/
バ is a katakana character with dakuten representing the sound /ba/
パ is a katakana character with handakuten representing the sound /pa/
ヴァ is a katakana combination using dakuten to represent the sound /va/
ネット is written in katakana and includes a sokuon mark (small ッ) to indicate a brief pause (geminated consonant)

Hentaigana 変体仮名

Non-standard kana characters that represent the same sounds as modern hiragana. Before standardization, Japanese had many kana variations for each sound. The kana system was later standardized by selecting a single hiragana and katakana form for each sound. Hentaigana still appear in historical texts and are occasionally used for stylistic purposes.

Examples:

𛀁 is a hentaigana corresponding to the hiragana character え derived from the kanji 江

Historical Kana 歴史的仮名遣い

Kana usage found in older forms of Japanese that differs from modern spelling. This includes characters that were used to write sounds that later merged in modern Japanese or historical spellings of Japanese words that do not reflect modern pronunciation.

Examples:

ゐ is a hiragana character used in historical Japanese writing to represent "wi", a sound that later merged with "i" in modern Japanese
ヱ is a katakana character used in historical Japanese writing to represent "we", a sound that later merged with "e" in modern Japanese
けふ is a historical kana spelling of 今日 that reflects an earlier pronunciation

Manyōgana 万葉仮名

Manyōgana are kanji characters used to write Japanese phonetically, regardless of the meaning of the kanji themselves. They are not kana themselves, but kana were later derived from them. Manyōgana also influenced later phonetic uses of kanji, such as phonetic ateji.

Examples:

Kanji such as 可 or 加 were used to represent the sound "ka", and the hiragana character か is derived from the cursive form of 加
Kanji such as 阿 or 安 were used to represent the sound "a", and the hiragana character あ is derived from the cursive form of 安
The phrase 波久比能海 from a Manyōshū poem is written in a combination of Manyōgana and semantic kanji (海, "ocean")

Furigana 振り仮名

Small kana written above or beside a word written with kanji to show its reading. When each kanji corresponds to part of the reading, furigana is sometimes written above each character individually. When the reading does not match the individual kanji (e.g., some ateji, gikun, jukujikun), furigana is written as one unit above the entire word instead. 振る historically meant "to assign" or "to attach", so furigana are kana added to kanji to show their reading.

Examples:

日ひ ("sun") is a word with furigana
日ひにち ("date") is a word written with both kanji and kana with furigana
絵え馬ま ("wooden prayer tablet") is a word with furigana above each character
今日きょう is a word with furigana above the whole word

Okurigana 送り仮名

The kana portion of a word written after a kanji. Okurigana distinguish between different words using the same kanji by showing part of the word's reading. They also indicate a word's conjugation (e.g., past vs. present tense, adjective vs adverb) by showing how the word changes form. In rare instances, two different words can have both the same kanji and the same okurigana. In these cases, the correct reading must be determined from context. 送る means "to send", so okurigana are the kana sent after a kanji to complete the word.

Examples:

生きる ("to live") is written with the okurigana きる to distinguish it from other words like 生える ("to grow")
The difference between the past-tense 作った ("made") and the present/future tense 作る ("to make") is shown through okurigana
The difference between the adjective 赤い ("red") and adverb 赤く ("red (adv.)") is shown through okurigana
抱く and 抱く are famously written with identical okurigana despite different pronunciations and meanings

Kanji Types

Root Character 根字

A kanji character that cannot be broken up meaningfully into components. There are generally two types of roots:

Characters that were originally a drawing of a single item, entity, or concept

Examples:

木 ("tree") is a drawing of a tree
象 ("elephant") is a drawing of an elephant

Compound characters that lost separability of their components due to changes in shape

See root by corruption

Root By Corruption 意味喪失による根字

A compound character that was changed such that one or more components became unrecognizable. Such characters are considered roots because they cannot be broken up meaningfully into components. This corruption of character's shape often occurs due to graphical stylization, sometimes as a form of simplification.

Examples:

光 used to be written closer to 灮 (火 ("fire") + 儿 (form of 人, "person")), but shape change made the top 火 portion unrecognizable
成 used to be written closer to 成 (戊 ("halberd") + 丁 ("ward", originally "nail")), but shape change made the 丁 unrecognizable
旅 used to be written closer to 𣃨 (㫃 ("flag") + 从 ("two people")), but shape change made the 从 unrecognizable

Compound Character 合体文字

A kanji character made up of more than one root or root form.

Examples:

明 ("light") is a compound of 日 ("sun") and 月 ("moon")
畑 ("field") is a compound of 火 ("fire") and 田 ("rice paddy")

Phono-Semantic Character 形声文字

A compound character that combines components that lend sound (phonetic components) with components that lend meaning (semantic components). The widespread development of phono-semantic characters displaced the Rebus Principle or kasha as a process for borrowing characters for new words based on similar pronunciation. Rather than use an existing character for a new word with a similar pronunciation, a new character was made using the existing character and another character chosen for either its meaning (semantic component) or its sound (another phonetic component) to differentiate the new character.

Examples:

If a picture of a "bee" were hypothetically used to denote "to be", the abstract meaning of "to be" could be applied to the "bee" picture and a new phono-semantic character could be created from "bee" + "beetle" for the meaning "bee" where the "beetle" qualifies the meaning as "insect-related"
切 ("to cut") was created from 七 ("seven", originally "to cut", phonetic + semantic) + 刀 ("knife", semantic) when 七 was borrowed to mean "seven"
鼻 ("nose") was created from 自 ("self", originally "nose", phonetic + semantic) + 畀 ("flathead arrow", phonetic) when 自 was borrowed to mean "self"
麦 ("wheat", originally "to come") was originally written closer to 麥 (来 (來, phonetic + semantic) + 夂 (semantic)) to distinguish it from 来 (來, "to come", originally "wheat"), but the two characters swapped places and 麦 qualified with a foot 夂 came to mean "wheat" instead of "to come"

Ryakuji 略字

A colloquial simplification of a kanji character. Ryakuji regularly appear in Japanese despite being unofficial characters and having limited support in computer fonts.

Examples:

々 is a ryakuji from 仝, a variant form of 同 ("the same"), used as a kanji duplication mark
〆 is a ryakuji from 占 ("to account for") used as a phonetic substitute for 締 ("to tighten") in 〆切り (締切り, "deadline")
ヶ is a ryakuji from 箇 (counter word) used as a counter in 一ヶ月 ("one month")

Punctuation & Symbols

Dakuten – "ten-ten" 濁点

Dakuten are a pair of dots placed at the upper right corner of a kana to indicate a voiced sound. They are used with the k-, s-, t-, and h-line kana. In non-standard usage, dakuten may also be applied to other kana, such as those in the a-line, to represent foreign sounds or for stylistic emphasis. Dakuten are colloquially known as "ten-ten" because they resemble two dots (点).

Examples:

が is か with dakuten
ザ is サ with dakuten
ヴァ is ウァ with dakuten on ウ
あ゙ is あ with dakuten, which is non-standard but occasionally appears in manga to indicate altered or emphasized pronunciation

Handakuten – "maru" 半濁点

Handakuten is a small circle placed at the upper right corner of a kana to indicate a p-sound. It is used with the h-line kana. In non-standard usage, handakuten may also be applied to other kana to represent sounds not captured by standard kana. Handakuten is colloquially known as "maru" because it resembles a circle (丸).

Examples:

ぱ is は with handakuten
ピ is ヒ with handakuten
か゚ is か with handakuten, a non-standard usage for denoting an /ŋ/ (ng) sound
ら゚ is ら with handakuten, a non-standard usage for denoting an /l/ sound

Sokuon – "small tsu" 促音

Sokuon is a brief pause (geminated consonant) that occurs before a consonant. The term can also refer to the sokuon mark (促音符), which is a small っ (hiragana) or ッ (katakana) used to indicate this pause in writing. It can also appear at the end of exclamations to indicate a sudden stop or emphasize surprise. Sokuon is colloquially known as 小さいつ, or "small tsu" in English.

Examples:

あっち ("over there") is written in hiragana with sokuon
ネット ("internet") is written in katakana with sokuon
あっ! ("Ah!") is an exclamation written in hiragana with sokuon to indicate a sudden stop or emphasize surprise
むっつ ("six things") is hiragana written with sokuon, while 六つ is written with kanji and okurigana, where the sokuon is not explicitly shown even though the sound is still present

Kana Duplication Mark 仮名の踊り字

Kana duplication marks are a set of symbols used to indicate that the preceeding kana is repeated. The hiragana duplication mark is ゝ, while the katakana duplication mark is ヽ. Additional marks exist for vertical writing. Kana duplication marks can take dakuten (ゞ and ヾ) to indicate that the repeated kana is voiced. These marks are uncommon in modern Japanese but still appear in names and historical writing. The term 踊り字 ("duplication mark") is based on the verb 踊る ("to dance") and reflects how these marks seem to "dance back" to repeat the previous character.

Examples:

サヽキ is a name written in katakana using a kana duplication mark
いすゞ is the official Japanese name of the car company Isuzu written in hiragana using a kana duplication mark with dakuten

Kanji Duplication Mark – "Noma" 漢字の踊り字

The kanji duplication mark is 々 and indicates that the preceeding kanji is repeated. This mark is typically used, but certain words with repeated kanji are conventionally written without it. The kanji duplication mark is colloquially known as "noma" because it resembles the katakana characters ノマ. The term 踊り字 ("duplication mark") is based on the verb 踊る ("to dance") and reflects how these marks seem to "dance back" to repeat the previous character.

Examples:

日々 ("days") uses the kanji duplication mark to repeat 日
時々 ("occasionally") uses the kanji duplication mark to repeat 時
所々 ("here and there") uses the kanji duplication mark to repeat 所
馬鹿々々しい ("foolish") uses the kanji duplication mark to repeat the preceding kanji in the compound 馬鹿 in combination with okurigana
九九 ("times tables") is a common word that is conventionally written without a duplication mark

Character Forms

Character Form 字体 + 部品の形

One of the many ways a kanji character can appear, either alone (字体) or as a component (部品の形). Both root characters and compound characters can have different character forms. Character forms generally fall into one of the following categories:

Alone (字体)

Traditional form
Simplified form
Kyūjitai form
Shinjitai form
Standard form
Variant form

As a component (部品の形)

Component form
Compressed component form
Variant component form

Traditional Form 繁体

An older character form that is not recognized as having been simplified. This term usually refers to characters used in Chinese language-speaking regions like Taiwan and Hong Kong where there was not a major writing system reform towards simplification (繁体字). In Japanese, this term overlaps significantly with the term "kyūjitai", meaning older forms of characters that were given newer "shinjitai" forms by law.

Examples:

龜 ("turtle") is the traditional form of 龟 (Chinese only)
馬 ("horse") is the traditional form of 马 (Chinese only)

Simplified Form 簡体

A newer character form that was created from a traditional character form, often to reduce character complexity. This term usually refers to characters used in Chinese language-speaking regions like Mainland China where a major writing system reform towards simplification has occured, typically by law (簡体字). In Japanese, this term is sometimes used to describe newer "shinjitai" forms of characters.

Examples:

连 (Chinese only) is the simplified form of 連 ("to take along")
读 (Chinese only) is the simplified form of 読 ("to read")

Kyūjitai Form 旧字体

An older form of Japanese kanji that contrasts with the newer "shinjitai" forms established by The Table of Character Forms for the Tōyō Kanji established in 1949. This term only applies to characters used in Japanese.

Examples:

龜 is the kyuujitai form of 亀 ("turtle")
國 is the kyuujitai form of 国 ("country")

Shinjitai Form 新字体

A newer form of an existing character that was established by The Table of Character Forms for the Tōyō Kanji in 1949. This term only applies to characters used in Japanese.

Examples:

会 ("meeting") is the shinjitai form of 會
学 ("study") is the shinjitai form of 學

Standard Form 正字

A character form (or set of forms) that is designated as standard, typically by law. In Japanese, standard kanji forms for print media were set by the Table of Character Forms for the Tōyō Kanji in 1949 and by the Jōyō Kanji List that later replaced it.

Examples:

神 ("god") is a standard form character even though the kyūjitai form 神 is also occasionally used
喜 ("joy") is a standard form character even though the variant form 㐂 is also occasionally used

Variant Form 異体字

A form of a character other than the accepted standard form.

Examples:

髙 is a variant form of 高 ("quantity") that appears in names and old writing
嶋 is a variant form of 島 ("island") that appears in names and old writing
﨑 is a variant form of 崎 ("peninsula") that appears in names and old writing

Corrupted Form 意味喪失の字体

A character form that has been graphically changed in a way that obscures the original meaning of the character's components and the reasoning behind its composition.

Examples:

光 ("light") is a corrupted form of its earlier form 灮 because graphical stylization of the top portion destroyed its relationship to the root 火 ("fire")
音 ("sound") is a corrupted form of its original composition (言 ("word") + 丶 ("dot"), a dot in the mouth of 言 to indicate "sound") because the current composition (立 ("to stand") + 日 (form of 曰, "to say")) obscures the reasoning behind the character

Component Form 部品の形

A form a character can take when used as a component within another character. Both root characters and compound characters can have component forms, and component forms cannot be used as stand-alone characters. Component forms come in two types:

Compressed component form (部品の圧縮形)

See compressed component form

Variant component form (部品の変形)

See variant component form

Compressed Component Form 部品の圧縮形

A component form that is written nearly identically to the stand-alone character but is compressed or distorted to fit a position within a compound character.

Examples:

⻗ is a compressed component form of 雨 ("rain")
訁 is a compressed component form of 言 ("word")
釒 is a compressed component form of 金 ("gold")

Variant Component Form 部品の変形

A component form that is visually different from its stand-alone form. Changes in singular stroke type (e.g., bottom stroke of 釒 vs 金) do not generally make a component form a variant. Variant component forms arose from graphical simplification of compressed component forms during the various stages of writing style evolution that led to the modern character forms.

Examples:

扌 is a variant component form of 手 ("hand")
氵 is a variant component form of 水 ("water")
⺩ is a variant component form of 玉 ("jewel")

Component Categories

Component 部品

A part of a kanji character that can do one of the following:

Appear alone as a different character

Examples:

門 ("gate") and 音 ("sound") are components of 闇 ("darkness")
山 ("mountain") and 風 ("wind") are components of 嵐 ("storm")

Be recognized as a form of a different character

Examples:

灬 is a form of 火 (ひ, "fire") and a component of 点 (てん, "dot")
扌 is a form of 手 (て, "hand") and a component of 持 (も[つ], "hold")

Semantic Component 意符

A component added to a kanji that relates to its meaning. All components that are not phonetic components are semantic components by default.

明 ("light"), 晴 ("to be sunny"), 曜 ("day") all share the semantic component 日 ("sun")
雰 ("atmosphere"), 雹 ("hail"), 霞 ("mist") all share the semantic component 雨 ("rain")
縦 ("warp"), 緯 ("weft"), 縫 ("to sew") all share the semantic component 糸 ("thread")
腕 ("arm"), 脚 ("leg"), 腰 ("hip") all share the semantic component ⺼, a form of 肉 ("meat")

Phonetic Component 音符

A component that either is present in a kanji or was present in its historical forms and that lends the kanji a similar reading or sound.

緋 ("crimson"), 誹 ("ridicule"), 匪 ("bandit") all share the phonetic component 非 ("not")
花 ("flower"), 貨 ("freight"), 靴 ("shoe") all share the phonetic component 化 ("change")
政 ("politics"), 征 ("subjugate"), 整 ("organize") all share the phonetic component 正 ("correct")
泊 ("overnight stay"), 舶 ("oceanliner"), 柏 ("oak") all share the phonetic component 白 ("white")

Stable Component 安定した部品

A component present in a kanji that has also been present in some or all forms of the character historically. (present before → present now)

Examples:

木 ("tree") is a stable component of 森 ("forest") because it has been present since the character's creation
心 ("heart") is a stable component of 悪 ("evil") because it has been present since the character's creation

Acquired Component 加わった部品

A component present in a kanji that was not historically present prior to a specific time point in the character's evolution. (not present before → present now)

Examples:

立 ("to stand") is an acquired component in 音 ("sound") because it arose through corruption of 言 (originally 言 ("word") + 丶 ("dot"))
乂 ("to mow") is an acquired component in 気 ("spirit") because it arose through simplification of 氣 ("spirit") (originally 气 ("air") + 米 ("rice"))
王 ("king") is an acquired component in 玉 ("jewel") because it arose through graphical stylization (originally unrelated)

Historical Component 失われた部品

A component not present in a kanji that was present in earlier historical forms of the kanji. (present before → not present now)

Examples:

言 ("word") is a historical component of 音 ("sound") because it was removed through corruption (originally 言 ("word") + 丶 ("dot"))
米 ("rice") is a historical component of 気 ("spirit") because it was replaced through simplification (originally 气 ("air") + 米 ("rice"))

False Component 見かけの部品

A component that appears to be present in a kanji but actually arises from misparsing the kanji's strokes. As a general rule, if removing a group of strokes leaves behind ungroupable strokes, the group is likely a false component.

Examples:

日 is a false component of 百 ("hundred") that misparses the component 白 (一 + 白)
少 is a false component of 雀 ("sparrow") that takes a stroke from 隹 (小 + 隹)

Pseudo-Component 擬似部品

A group of strokes that appears to be a component but fails to meet the definition because it is neither a stand-alone character nor a form of a stand-alone character. Pseudo-components are typically only part of a root but appear component-like because they are shared among characters that are similar in shape but that are historically unrelated.

Examples:

亠 is a pseudo-component that is part of roots like 六 ("six"), 交 ("to be mixed"), 京 ("capital"), and 高 ("quantity") that share a stylized top portion
龷 is a pseudo-component that is part of roots like 共 ("together") and 昔 ("long ago") that share a stylized top portion

Reading & Meaning Terms

Rebus Principle レブス原理

A technique for expanding the meaning of a symbol or character by using it to represent a different word that sounds similar. It played an important role in allowing pictographic writing systems to represent abstract ideas that could not be directly depicted. In the context of kanji characters, the Rebus Principle is called kasha.

Examples:

A drawing of a soup can to indicate "can", as in "is possible"
A drawing of a bee to indicate "to be"

Kasha 仮借

The use of a kanji character for another meaning because of a similar pronunciation. This is a kanji-specific term for the Rebus Principle. In contrast to ateji, which describes the assignment of Japanese word readings to existing characters, kasha primarily describes the borrowing of existing characters for new words during the early development of the Chinese writing system. The kasha process was later largely displaced by the widespread development of phono-semantic characters, which combine phonetic borrowing with semantic qualifiers.

Examples:

A drawing of wheat 来 (來) used to write 来る ("to come") because of similar pronunciation in Old Chinese
A drawing of a nose 自 used to write "self" because of similar pronunciation in Old Chinese

On-reading 音読み

A kanji reading based on historical Chinese pronunciations. The character 音 means "sound" and points to the idea of reading characters based on their associated (Chinese-derived) sounds.

Examples:

豆 ("bean") has the on-readings トウ and ズ
港 ("harbor") has the on-reading コウ
楓 ("maple") has the on-reading フウ

Kun-reading 訓読み

A kanji reading derived from a native Japanese word (wago). Kun-readings can be categorized as either standalone (full word) or stem (part of a word) kun-readings. The character 訓 means "to explain" and points to the idea of reading characters in a way that reflects their meaning in native Japanese words.

Examples:

豆 ("bean") has the kun-reading まめ
港 ("harbor") has the kun-reading みなと
楓 ("maple") has the kun-reading かえで

Standalone Kun-reading 単独の訓読み

A kun-reading that can appear as an independent word (i.e., written without okurigana or additional kanji). This includes readings that can appear as independent words, even if they are also used as prefixes or suffixes. Minor sound changes when attaching to other words do not affect this classification.

Examples:

火 ("fire") has the standalone kun-reading ひ
火花 ("spark") is a kanji compound that uses the standalone kun-readings ひ and はな (appearing as -ばな because of rendaku)
生放送 ("live broadcast") is a kanji compound that uses the standalone kun-reading なま as a prefix
六つ ("six things") uses the standalone kun-reading むい (minor sound change to むっ when attaching) and the general counter つ

Stem Kun-reading 語幹の訓読み

A kun-reading that appears as part of a word requiring additional kana or other elements to be complete. Stem kun-readings are often followed by okurigana indicating conjugation, but they may also appear without visible okurigana when combined with other words or when okurigana are abbreviated in writing. These cases do not affect the classification. Because kanji are used to represent the meaning of existing words, stem kun-readings are not always predictable from the kanji alone and can be shared across many kanji used to write the same word. Some readings are used as both standalone and stem kun-readings, particularly when the same reading appears in both noun and verb or adjective forms.

Examples:

生む ("to birth"), 生える ("to grow"), and 生きる ("to live") are different stem kun-readings for when 生 ("life") is used to write different words
取る ("to take"), 採る ("to gather"), 捕る ("to catch"), and 撮る ("to take a photo") share the stem kun-reading と[る] because they represent the same core verb with different nuances depending on the kanji used
太い ("thick") and 太る ("to fatten") are adjective and verb forms built from the stem kun-reading ふと
太股 ("thigh") uses the stem kun-reading ふと without conjugation
赤 ("red") has the kun-reading あか, which can function as both a standalone kun-reading and a stem kun-reading (赤い and 赤らむ)
締切り ("deadline") uses the stem kun-reading し (from 締める) with abbreviated okurigana

Ateji 当て字・充て字

An assignment (当てる) of characters for a word based on either the characters' sounds or their meanings. In contrast to jukujikun, which generally assign Japanese words to existing character compounds from Chinese (characters → word), ateji generally seeks characters for existing words (word → characters)..

Examples:

寿司 is written as 寿 ("longevity") + 司 ("office"), both used for sound
煙草 (タバコ) can be written as 煙 ("smoke") + 草 ("grass"), both used for their meanings
硝子 (ガラス) can be written as 硝 ("saltpeter") + 子 ("child"), 硝 for meaning and 子 for sound

Jukujikun 熟字訓

A kun-reading that spans multiple characters. In contrast to ateji, which generally assigns characters for existing words (word → characters), jukujikun generally assign Japanese words to existing character compounds from Chinese (characters → word).

Examples:

大人 is read おとな, which cannot be divided by character
今日 is read きょう, which cannot be divided by character
田舎 is read いなか, which cannot be divided by character

Gikun 義訓

A reading assigned to a kanji word based on an associated meaning (義). Gikun readings partially overlap with Jukujikun readings in that they both assign readings to existing character compounds (characters → word) based on the characters' associated meaning.

Examples:

身体 is sometimes read からだ (体) because both mean "body"
牛乳 is sometimes read ミルク because both mean "milk"
智慧之王 ("Lord of Wisdom") is read as ラファエル ("Rafael") in "That Time I Got Reincarnated as a Slime" because "Lord of Wisdom" and "Rafael" are intended to be synonymous by the author

Rendaku 連濁

Rendaku is a change in pronunciation in which the initial consonant of the second part of a compound word becomes voiced. It commonly occurs in Japanese compound words but does not apply in all cases and is not fully predictable. In writing, rendaku is reflected by adding dakuten to the affected kana.

Examples:

In 花火 ("firework"), the second character 火 is pronounced び due to rendaku
In 火花 ("spark"), the second character 花 is pronounced ばな due to rendaku
In 手紙 ("letter"), the second character 紙 is pronounced がみ due to rendaku

Duplicative Voicing 重複語の連濁

Duplicative voicing is a change in pronunciation in which the initial consonant of the second instance of a repeated word becomes voiced. This is a fairly stable behavior and occurs in most cases of reduplication where the second consonant has a voiced counterpart.

Examples:

In さまざま ("various"), the second instance is pronounced ざま due to duplicative voicing
In 日々 ("days"), written with the duplication mark 々, the second instance of 日 is pronounced び due to duplicative voicing
In 人々 ("people"), written with the duplication mark 々, the second instance of 人 is pronounced びと due to duplicative voicing
In 山々 ("very much"), written with the duplication mark 々, the second instance of 山 is not voiced because y-sounds do not have voiced equivalents in Japanese

Word Categories

Wago 和語

Native Japanese words, also called Yamato words (大和言葉) after the Yamato (大和) majority ethnic group of Japan. The Yamato ethnic group formed during the Yayoi (弥生) and Kofun (古墳) periods through migrations from mainland China and Korea, displacing the pre-existing Jōmon (縄文) people and forming the Japanese language. This category includes all Japanese words that are not derived from loan words.

Examples:

くるま (車) is a native Japanese word meaning "car"
いぬ (犬) is a native Japanese word meaning "dog"
さくら (桜) is a native Japanese word meaning "cherry blossom"

Loan Word 借用語

A word that is borrowed from another language. This is a broader category than gairaigo and includes both recently borrowed words and older assimilated words (including kango and words from early Portuguese contact).

Examples:

パン is a loan word from the Portuguese word "pão" ("bread")
天ぷら is a loan word from the Portuguese word "tempora" ("time", referring to the Ember Days when fried foods were eaten)
煙草 (タバコ) is a loan word from the Portuguese word "tabaco" ("tobacco")
文化 is a loan word from the Chinese word 文化 (wénhuà, "culture")

Gairaigo 外来語

Japanese words that are borrowed forms of foreign words. This is a narrower category than general loan words and typically refers to newer foreign words that are widely recognized as being foreign in origin. As words assimilate, they gradually stop being gairaigo but are still considered loan words.

Examples:

コンピューター is a gairaigo from the English word "computer"
レストラン is a gairaigo from the French word "restaurant"
アルバイト is a gairaigo from the German word "arbeit" ("work")
イクラ is a gairaigo from the Russian word "ikra" ("salmon roe")

Kango 漢語

Japanese words that originate from Chinese loan words.

Examples:

社会 ("society") is a kango from the Chinese word 社会 (shèhuì, "society")
経済 ("economy") is a kango from the Chinese word 經濟 (jīngjì, "economy")
政治 ("politics") is a kango from the Chinese word 政治 (zhèngzhì, "politics")

Hybrid Word 混種語

A word that combines parts borrowed from at least 2 different languages.

Examples:

カップ麺 ("cup noodles") is a hybrid word from カップ (English "cup") + 麺 (Chinese miàn, "noodle")
製パン ("breadmaking") is a hybrid word from 製 (Chinese zhì, "to manufacture") + パン (Portuguese "pão", "bread")
サボる ("to sabotage") is a hybrid word from サボ (abbreviated form of サボタージュ, English "sabotage") + る (Japanese verb ending)

Abbreviated Word 省略語

A word formed by shortening another existing word.

Examples:

コンビニ ("convenience store") is an abbreviated form of the English loan word コンビニエンスストア
テレビ ("television") is an abbreviated form of the English loan word テレビジョン
アニメ ("anime") is an abbreviated form of the English loan word アニメーション