Open English Wordnet
Nouns
(n)spy, undercover agent(military) a secret agent hired by a state to obtain information about its enemies or by a business to obtain industrial secrets from competitors (n)spya secret watcher; someone who secretly watches other people“my spies tell me that you had a good time last night” Verbs
(v)spy, sightcatch sight of; to perceive with the eyes“he caught sight of the king's men coming over the ridge” (v)spysecretly collect sensitive or classified information; engage in espionage“spy for the Russians”