The yō-on (Japanese: 拗音 (ようおん)), also written as yōon, is a feature of the Japanese language in which a mora is formed with an added [j] sound, i.e., palatalized, or (more rarely in the modern language) with an added [w] sound, i.e. labialized.

Yōon are represented in hiragana using a kana ending in i, such as き (ki) or に (ni), plus a smaller version of one of the three y kana, ya, yu or yo. For example, kyō, "today" (今日), is written きょう [kʲoo], using a small version of the yo kana, よ. Contrast this with kiyō, "skillful" (器用), which is written きよう [kijoo], with a full-sized yo kana. In historical kana orthography, yōon were not distinguished with the smaller kana, and had to be determined by context.

In earlier stages of Japanese, and in certain dialects, yōon can also be formed with the kana wa, wi, we, and wo; for example, くゎ/クヮ kwa, く/ク kwi, く/ク kwe, く/ク kwo[citation needed]. Although obsolete in modern Japanese, kwa and kwi can still be found in several of the Ryukyuan languages today (e.g. Okinawan), while kwe is formed with the digraph くぇ. Instead of the kana き, these are formed with the kana for ku, く/ク.

Table edit

Yōon (拗音)
ya yu yo
ki キャ kya キュ kyu キョ kyo
shi シャ sha シュ shu ショ sho
chi チャ cha チュ chu チョ cho
ni ニャ nya ニュ nyu ニョ nyo
hi ヒャ hya ヒュ hyu ヒョ hyo
mi ミャ mya ミュ myu ミョ myo
ri リャ rya リュ ryu リョ ryo
gi ギャ gya ギュ gyu ギョ gyo
ji ジャ ja ジュ ju ジョ jo
ji ヂャ ja ヂュ ju ヂョ jo
bi ビャ bya ビュ byu ビョ byo
pi ピャ pya ピュ pyu ピョ pyo
ya yu yo
ki きゃ kya きゅ kyu きょ kyo
shi しゃ sha しゅ shu しょ sho
chi ちゃ cha ちゅ chu ちょ cho
ni にゃ nya にゅ nyu にょ nyo
hi ひゃ hya ひゅ hyu ひょ hyo
mi みゃ mya みゅ myu みょ myo
ri りゃ rya りゅ ryu りょ ryo
gi ぎゃ gya ぎゅ gyu ぎょ gyo
ji じゃ ja じゅ ju じょ jo
ji ぢゃ ja ぢゅ ju ぢょ jo
bi びゃ bya びゅ byu びょ byo
pi ぴゃ pya ぴゅ pyu ぴょ pyo
合拗音 (Gō Yōon, Closed Yōon) – Obsolete
labialized k くゎ kwa (くkwi (くkwe
labialized g ぐゎ gwa (ぐgwi (ぐgwe

Other representations edit

Yōon Yōon + Dakuten Yōon + Handakuten -w-

In Japanese Braille, Yōon is indicated with one of the yōon, yōon+dakuten, or yōon+handakuten prefixes.

Unlike in kana, Braille yōon is prefixed to the -a/-u/-o syllables, rather than appending ya, yu or yo to an -i kana, e.g. kyu: きゅ - ki + yu - yōon + ku. Likewise, the -w- syllables are indicated by a prefix of the -a/-i/-e/-o syllables, rather than an -u syllable, e.g. くぁ / くゎ (kwa) = -w- + ka: .