sài

compete

Original meaning: 

thank offering

Phonosemantic compound. represents the meaning and represents the sound. Based on the original meaning "thank offering". The meaning later shifted to "compete".

Components
塞 sound,remnant component

  Sound Remnant component

sāisài

  

stop up

貝 meaning component

  Meaning component

bèi

  

sea shell

Shells were used as currency in ancient China.

Evolution

賽 Seal script Shuowen (~100 AD)

Seal script

Shuowen (~100 AD)
賽 Regular script Modern

Regular script

Modern
Definitions

() 

sài

compete, contend; contest, race; to compete; competition; match; to surpass; better than; superior to; to excel

Most common words with 賽
Freq.
Word
Meaning

比赛

match

match

决赛

finals (of a competition)

联赛

(sports) league

赛季

season (sports)