Simplified form of 離. Depicts a bird (隹) being caught in a bird trap (罕). Based on the original meaning "catch a bird". The meaning later shifted to "reject", "separate", and "leave". The 隹 (bird) component was removed for simplification.

Evolution

Bronze script

Late Warring States (~250 BC)

Seal script

Shuowen (~100 AD)

Clerical script

Western Han dynasty (202 BC-9 AD)

Regular script

Modern