Phonosemantic compound. ⺮ represents the meaning and 間 represents the sound. The character is based on the original meaning "bamboo strips for writing". The meaning later shifted to "letter", "concise", and "simple".

Evolution

Bronze script

Late Western Zhou (~800 BC)

Seal script

Shuowen (~100 AD)

Clerical script

Eastern Han dynasty (25-220 AD)

Regular script

Modern

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