work time vs turnaround

work time and turnaround both are nouns.

Word	Noun	Adjective	Verb	Adverb
work time	Yes	No	No	No
turnaround	Yes	No	No	No

As nouns, turnaround is a hyponym of work time; that is, turnaround is a word with a more specific, narrower meaning than work time:

Other hyponyms of work time include hours, face time, week, workweek, day, overtime, turnaround time.

work time (noun)	turnaround (noun)
a time period when you are required to work	turning in the opposite direction
	act or process of unloading and loading and servicing a vessel or aircraft for a return trip
	an area sufficiently large for a vehicle to turn around
	a decision to reverse an earlier decision
	time need to prepare a vessel or ship for a return trip