What is the difference between peak, peek, and pique?
A mountain or something that looks like one (whipped egg whites, for instance) or a metaphorical high point is a peak. It can also be used as an adjective, as in "peak condition", and a verb, as in "athletes train to peak for the Olympic Games".
A quick look is a peek. This can also be used as a verb, as in "he peeked around the corner". If you have a hard time remembering that it's spelled with a double e, think of other words that have to do with seeing things: see, seek, peer, even leer if that helps (hey, whatever it takes...)
If you're angry or resentful, you're having a fit of pique. If something makes you interested, it piques your interest. This is a fairly old word in English, coming from Middle French pique a quarrel, resentment, which in turn came from piquer to prick, pierce, sting.
It is apparently quite common for people to misspell "pique" too, writing "it peaked my interest", possibly thinking that the phrase means "bring one's interest to a high point". But it doesn't mean that. Perhaps thinking of the etymologically related word "piquant" will help. Food that is piquant stimulates your appetite for more, just as something that piques your interest makes you want more.
So if taking a quick look at a mountain makes you want to know more, you could say your curiosity was piqued by peeking at a peak!
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