noun, plural spies.
verb (used without object), spied, spy·ing.
verb (used with object), spied, spy·ing.
Origin of spy
noun plural spies
verb spies, spying or spied
Word Origin for spy
mid-13c., from Old French espier "to spy," probably from Frankish *spehon, from Proto-Germanic *spekh- (cf. Old High German *spehon "to look out for, scout, spy," German spähen "to spy," Middle Dutch spien), the Germanic survivals of the productive PIE root *spek- "to look" (see scope (n.1)).
mid-13c., "one who spies on another," From Old French espie, probably from a Germanic source (see spy (v.)).
Secretly or furtively observe someone or something, as in The children loved spying on the grownups, or The company sent him to spy on the competitor's sales force. [Early 1600s]