Dictionary definition · spy
noun
- (military) a secret agent hired by a state to obtain information about its enemies or by a business to obtain industrial secrets from competitors
- a secret watcher; someone who secretly watches other people"my spies tell me that you had a good time last night"
verb
- catch sight of
- watch, observe, or inquire secretly
- catch sight of; to perceive with the eyes"he caught sight of the king's men coming over the ridge"
- secretly collect sensitive or classified information; engage in espionage"spy for the Russians"
Source: Open English WordNet (CC BY 4.0).