xū
need
Original meaning:
become wet
Pictograph of a person standing under the rain (雨), representing the meaning "become wet", now written as 濡. The current meaning is a phonetic loan. The person component was later replaced with the phonetic component 而.
Evolution

Bronze script
Early Western Zhou (~1000 BC)
Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Regular script
ModernDefinitions
Sources