Caught sight of something or someone, often suddenly or unexpectedly; past tense of spy.
From Old French 'espier' meaning 'to watch or observe.' Originally related to military reconnaissance, the word evolved from Germanic roots and eventually came to mean any act of seeing or noticing.
The word 'spy' started as a verb meaning simply 'to see or catch sight of,' which is why you 'spy' something when you spot it—the espionage meaning came much later as an extension of the observation idea.
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