spotter vs discoverer

spotter and discoverer both are nouns.

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

As nouns, spotter and discoverer are synonyms defined as:

Other synonyms of spotter include finder.

spotter (noun)	discoverer (noun)
someone who is the first to observe something	someone who is the first to observe something
a worker employed to apply spots (as markers or identifiers)	someone who is the first to think of or make something
a worker employed at a dry-cleaning establishment to remove spots
a person employed to keep watch for some anticipated event