pǒu

to spit out

Original meaning: 

not

Originally the same character as . A distinguishing mark was added later to the character to differentiate it from . The current meaning "to spit out" is a phonetic loan.

Components
丶 distinguishing component

  Distinguishing component

zhǔ

  

dot

Mark used to differentiate from .

否 sound,meaning component

  Sound Meaning component

fǒu

  

not

Evolution

咅 Bronze script Late Spring and Autumn (~500 BC)

Bronze script

Late Spring and Autumn (~500 BC)
咅 Seal script Shuowen (~100 AD)

Seal script

Shuowen (~100 AD)
咅 Seal script Shuowen (~100 AD)

Seal script

Shuowen (~100 AD)
咅 Clerical script Qin dynasty (221-206 BC)

Clerical script

Qin dynasty (221-206 BC)
咅 Regular script Modern

Regular script

Modern
Definitions

 

pǒu

to spit out; pooh; pah; bah; (today used as a phonetic component in [bù], [bèi], [péi], [pōu] etc)

Component uses

Sound component in 16 characters (4 verified)

Sources

李学勤《字源》p.448