1. indicates emotion or admirationFemale term or language, at sentence end
2. indicates emphasisKansai dialect, at sentence end
3. wah!
4. boo!
Wikipedia definition
5. Wa (kana)わ, in hiragana, or ワ in katakana, is one of the Japanese kana, which each represent one mora. It represents [wa wa] and has origins in the character 和. There is also a small ゎ/ヮ, that is used to write the morae /kwa/ and /gwa/ (くゎ, ぐゎ), which are obsolete in contemporary standard Japanese but still exist in the Ryukyuan languages. Katakana ワ is also sometimes written with dakuten, ヷ, to represent a /va/ sound in foreign words; however, most IMEs lack a convenient way to write this.
Read “Wa (kana)” on English Wikipedia
Read “わ” on Japanese Wikipedia
Read “Wa (kana)” on DBpedia


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