This rare kanji has no clear standalone meaning. Treat its meaning as uncertain.
哳 is a rare character composed of 口 (mouth) and 折 (break, fold). The exact historical development is uncertain, and it may have originally represented a sound or a specific word now obscure.
With 口 (mouth) beside 折 (break), imagine a mouth breaking into a sudden, sharp sound—perhaps a chirp or a crackle—though the true meaning is unclear.
For タツ, picture a mouth (口) breaking (折) into a loud 'tats!' sound, like a sharp clap or snap: tats -> タツ.
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