Pictograph of a woman (母) with a hairpin in her hair. In ancient China, women of marriageable age wore a hairpin. Based on the original meaning "young woman" The current meaning is a phonetic loan.

Evolution

Oracle script

(~1250-1000 BC)

Bronze script

Early Western Zhou (~1000 BC)

Seal script

Shuowen (~100 AD)

Clerical script

Eastern Han dynasty (25-220 AD)

Regular script

Modern

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