lookout vs lookout man

lookout and lookout man both are nouns.

Word	Noun	Adjective	Verb	Adverb
lookout	Yes	No	No	No
lookout man	Yes	No	No	No

As nouns, lookout and lookout man are synonyms defined as:

lookout and lookout man: a person employed to keep watch for some anticipated event

Other synonyms of lookout include picket, scout, sentinel, sentry, spotter, watch.

lookout (noun)	lookout man (noun)
the act of looking out	a person employed to keep watch for some anticipated event
a structure commanding a wide view of its surroundings
an elevated post affording a wide view
a person employed to keep watch for some anticipated event