wèi
not yet
Original meaning:
tree trunk
Similar to 木 (tree), with extra branches added. Based on the original meaning "tree trunk", now written as 枚. The current meaning is a phonetic loan.
Evolution

Oracle script
(~1250-1000 BC)
Bronze script
Early Western Zhou (~1000 BC)
Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Regular script
ModernDefinitions
wèi
not yet; 8th terrestrial branch; did not; have not; not; 8th earthly branch: 1-3 p.m., 6th solar month (7th July-6th August), year of the Sheep; ancient Chinese compass point: 210°
Component uses
Meaning component in 1 character (0 verified)
Iconic component in 1 character (1 verified)
Sources
季旭昇《說文新證》p.981