To look at something quickly and secretly, usually just for a moment and often without wanting to be noticed.
From Middle English 'peken,' possibly related to 'pick.' The word arose in English around 1500s, originally describing a cautious quick glance, often with the idea of hiding the action.
Peek and peak sound the same but mean opposite things—peek is looking quickly, peak is the highest point. They're called homophones, and English is full of these tricky pairs that trip up learners.
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