Yōon
The is a feature of the Japanese language in which a mora is formed with an added sound, i.e., palatalized, or with an added sound, i.e. labialized.
are represented in hiragana using a kana ending in, such as き or に, plus a smaller version of one of the three kana, や, ゆ or よ. For example, 今日 is written, using a small version of the よ kana. Contrast this with, which is written きよう, with a full-sized よ kana. In historical kana orthography, were not distinguished with the smaller kana, and had to be determined by context.
In earlier stages of Japanese, and in certain dialects, can also be formed with the kana,,, and ; for example, くゎ/クヮ, くゐ/クヰ, くゑ/クヱ, くを/クヲ. Although obsolete in modern Japanese, and can still be found in several of the Ryukyuan languages today, while is formed with the digraph くぇ. also appears in the Kagoshima dialect. Instead of the kana き, these are formed with the kana for, く/ク. Some older transliterations in English follow the earlier pronunciation, e.g.,, and such may appear in loanwords e.g. ムジカ・アンティクヮ・ケルン "Musica Antiqua Köln". They were also used to write Hakka in Taiwan under Japanese rule.
Table
| ゎ wa | ゐ wi | ゑ we | |
| く ku | くゎ kwa | kwi | kwe |
| ぐ gu | ぐゎ gwa | gwi | gwe |
Other representations
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 morae, rather than appending ya, yu or yo to an -i kana, e.g. kyu: きゅ - ki + yu → - yōon + ku. Likewise, the -w- morae are indicated by a prefix of the -a/-i/-e/-o morae, rather than an -u mora, e.g. くぁ / くゎ = -w- + ka:.