jǐ, jī
how much
Original meaning:
danger
Depicts a weapon (戈) cutting ropes (𢆶) tied around a person (人). Based on the original meaning "danger". The current meaning is a phonetic loan.
Evolution

Bronze script
Mid Western Zhou (~900 BC)
Seal script
Shuowen (~100 AD)
Clerical script
Qin dynasty (221-206 BC)Regular script
ModernDefinitions
Sources
季旭昇《說文新證》p.318-319