also checkup, "careful examination," 1921, American English, from the verbal phrase (1889), from check (v.1) + up (adv.), on notion of a checklist of things to be examined. The verbal phrase check up (on) is attested from 1889.
checkers
check-list
checkmate
checkout
checkpoint
check-up
cheddar
cheek
cheeks
cheeky
cheep