lookout vs spotter

lookout and spotter both are nouns.

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

As nouns, lookout and spotter are synonyms defined as:

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

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

lookout (noun)	spotter (noun)
the act of looking out	someone who is the first to observe something
a structure commanding a wide view of its surroundings	a worker employed to apply spots (as markers or identifiers)
an elevated post affording a wide view	a worker employed at a dry-cleaning establishment to remove spots
a person employed to keep watch for some anticipated event	a person employed to keep watch for some anticipated event