time clock vs clock

time clock and clock both are nouns.

Word	Noun	Adjective	Verb	Adverb
time clock	Yes	No	No	No
clock	Yes	No	Yes	No

As nouns, clock is a hypernym of time clock; that is, clock is a word with a broader meaning than time clock:

time clock (noun)	clock (noun)
clock used to record the hours that people work	a timepiece that shows the time of day

time clock (verb)	clock (verb)
	measure the time or duration of an event or action or the person who performs an action in a certain period of time