/ ˈspɒtə(r); NAmE ˈspɑːt-/ noun
1.
(especially in compounds) a person who looks for a particular type of thing or person, as a hobby or job :
a talent spotter (= sb who visits clubs and theatres looking for new performers)
—see also trainspotter
2.
(also ˈspotter plane ) a plane used for finding out what an enemy is doing