bleat
哶 represents the sound of a bleat, like a sheep or goat. Its meaning is tied to that specific animal cry.
哶 is a phono-semantic compound with 口 (mouth) and a phonetic component related to 羊 (sheep), indicating the bleating sound of a sheep.
The mouth radical 口 on the left and the sheep-like shape on the right suggest the sound a sheep makes: a bleat.
For バ, imagine a sheep going 'baa' as it bleats: baa -> バ, and the mouth radical 口 shows the sound.
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