zèng
boiler for steaming rice
Phonosemantic compound. 瓦 represents the meaning and 曾 represents the sound. Originally written as 曾.
Evolution

Seal script
Shuowen (~100 AD)
Seal script
Shuowen (~100 AD)
Clerical script
Western Han dynasty (202 BC-9 AD)
Clerical script
Western Han dynasty (202 BC-9 AD)Regular script
ModernDefinitions
Sources