kāi
open
Simplified form of 開. Pictograph of two hands (廾) opening the bolt (一) on a door (門). The traditional component 門 was removed for simplification.
Components
Evolution

Seal script
Shuowen (~100 AD)
Clerical script
Eastern Han dynasty (25-220 AD)Traditional script
ModernSimplified script
ModernDefinitions
Component uses
Sources
季旭昇《說文新證》p.836