Su (kana)
Su is one of the Japanese kana, each of which represents one mora. Their shapes come from the kanji 寸 and 須, respectively. Both kana represent the sound. In the Ainu language, the katakana ス can be written as small ㇲ to represent a final s and is used to emphasize the pronunciation of rather than the normal .
| Forms | Rōmaji | Hiragana | Katakana |
| Normal s- | su | す | ス |
| Normal s- | suu, swu sū | すう, すぅ すー | スウ, スゥ スー |
| Addition dakuten z- | zu | ず | ズ |
| Addition dakuten z- | zuu, zwu zū | ずう, ずぅ ずー | ズウ, ズゥ ズー |