clock watcher vs layabout

clock watcher and layabout both are nouns.

Word	Noun	Adjective	Verb	Adverb
clock watcher	Yes	No	No	No
layabout	Yes	No	No	No

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

Other hypernyms of clock watcher include bum, do-nothing, idler, loafer.

clock watcher (noun)	layabout (noun)
a worker preoccupied with the arrival of quitting time	person who does no work