Phonosemantic compound. 穴 represents the meaning and 切 represents the sound. Based on the original meaning "to steal rice". The meaning of this character has shifted over time and now means "secretly". Simplified form of 竊.

Evolution

Seal script

Shuowen (~100 AD)

Clerical script

Eastern Han dynasty (25-220 AD)

Traditional script

Modern

Simplified script

Modern

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