xī
west
西 was written two different ways in ancient scripts: (1) a pictograph of a bird's nest, and (2) a variant of the phonetically similar 囟.
Evolution

Oracle script
(~1250-1000 BC)
Bronze script
Late Shang dynasty (~1100 BC)
Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Regular script
ModernDefinitions
Component uses
Simplified component in 1 character (1 verified)
Unknown component in 1 character (1 verified)
Sources
季旭昇《說文新證》p.831-832