watcher vs lookout

watcher and lookout both are nouns.

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

As nouns, lookout is a hyponym of watcher; that is, lookout is a word with a more specific, narrower meaning than watcher:

watcher (noun)	lookout (noun)
a guard who keeps watch	the act of looking out
a close observer; someone who looks at something (such as an exhibition of some kind)	a structure commanding a wide view of its surroundings
a person who keeps a devotional vigil by a sick bed or by a dead body	an elevated post affording a wide view
	a person employed to keep watch for some anticipated event