n. & v.
--n. (pl. spies)
1. a person who secretly collects and reports information on the activities, movements, etc., of an enemy, competitor, etc.
2 a person who keeps watch on others, esp. furtively.
--v. (spies, spied)
1. tr. discern or make out, esp. by careful observation (spied a house in the distance).
2 intr. (often foll. by on) act as a spy, keep a close and secret watch.
3 intr. (often foll. by into) pry.
Phrases and idioms:
I spy a children's game of guessing a visible object from the initial letter of its name. spy-master colloq. the head of an organization of spies. spy out explore or discover, esp. secretly.
Etymology: ME f. OF espie espying, espier espy f. Gmc