bleat of sheep, surname
羋 centers on the sound a sheep makes: a bleat. It is also used as a surname, likely derived from that bleating sound or an associated clan.
羋 is a pictograph of a sheep's head with horns, representing the bleating sound. The surname usage is ancient and likely connected to a clan name.
The top part looks like a sheep's face with two horns (卝) and the vertical line (丨) is its body. Imagine a sheep standing there, bleating.
For バ, picture a sheep bleating 'baa baa': baa -> バ, the sound of the sheep.
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