caddy 
cali 
captain obvious 
catch ya later 
catfish
celly
 
cha-ching 
check it out 
cheers 【ベスト100スラング48位】
cheugy/cheug  [2021]
chi town
 
chick 
chill out 
chuuch 
cig 
clapback
climb the wall
cold turkey 
Come again? [2021]
congrats
cool beans, kool beans 
crap 
cray / cray cray
crib 
cringe / cringe-worthy 
Cross that bridge when you come to it. [2021]
crunk