Overview
Wu (hiragana: 𛄟, katakana: 𛄢) is a hentaigana, a variant kana or Japanese syllable.
History
It is presumed that 𛄟 would have represented . Along with 𛀆 and 𛀁 (yi and ye respectively), the syllable wu has no officially recognized kana, as these syllables do not occur in native Japanese words; however, during the Meiji period, linguists almost unanimously agreed on the kana for yi, ye, and wu. 𛀆 and wu are thought to have never occurred as syllables in Japanese, and 𛀁 was merged with え and エ.
Characters
In the Edo period and the Meiji period, some Japanese linguists tried to separate kana u and kana wu. The shapes of characters differed with each linguist. 𛄟 and 𛄢 were just two of many shapes.
They were phonetic symbols to fill in the blanks of the gojuon table. Japanese people didn't separate them in normal writing.
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