Phonosemantic compound. 牛 represents the meaning and 勿 represents the sound. Based on the original meaning "variety", depicting the variety of colors on a cow. Later the meaning shifted to "things".

Evolution

Oracle script

(~1250-1000 BC)

Seal script

Shuowen (~100 AD)

Clerical script

Western Jin dynasty (266-316 AD)

Regular script

Modern

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