The other reason this particular set of homonyms irritates me is that for every person who goes "Ohhhhh, gotcha, thanks!" when the error is pointed out, there is usually one person who will attempt to justify the mistake by trying to equate the definition of the word they've misused with the intent behind the sentence. But they're still wrong. Let me tell you how and why.
I am far from a grammarian, and although I know plenty about proper word usage (most of the time - Robb Grindstaff has to remind me about farther/further every time!) my eyes have been known to glaze over at some of the more complicated discussions of syntax and such. I don't want YOUR eyes to glaze over here, but in order to finally put the peak/peek/pique thing to rest, we'll have to dig into transitive and intransitive verbs a little bit, in addition to the actual meanings of the words.
A transitive verb is one that takes a direct object. She left the door open. Here, left is a transitive verb, because it takes the object the door. The action is being performed directly on the door. The sentence would be incomplete if there weren't an object to go with that verb.
Intransitive verbs do not take a direct object, and are complete without one. Intransitive verbs are (often, I'm not sure if they are always) a state of being. The action is not being performed directly to or on someone/something. She left at intermission. Here, left is an intransitive verb. There is no direct object.
If you aren't sure whether a verb is transitive or intransitive, try to reword the sentence in passive voice, using "by". If you can, it's transitive. If not, it's intransitive. The door was left open by her make sense. You can't rewrite the second sentence in the same way because it's an intransitive verb.
So what does this have to do with peak/peek/pique?
First of all, let's just throw out peek from this equation because we all know the verb to peek means to glance quickly. It is occasionally used instead of peak, but nobody has ever tried to use the different meanings of peek and peak to justify their misuse. It's mostly a spelling error. Though I hold you, dear readers, to a higher standard, so I really hope you're using that one correctly. ;-)
The big two offenders are peak and pique, which people seem to confuse not only in spelling, but meaning.
verb (used with object)
1. to affect with sharp irritation and resentment, especially by some wound to pride: She was greatly piqued when they refused her invitation.
2. to wound (the pride, vanity, etc.).
3. to excite (interest, curiosity, etc.): Her curiosity was piqued by the gossip.
4. to arouse an emotion or provoke to action: to pique someone to answer a challenge.
5. Archaic . to pride (oneself) (usually followed by on or upon ).
verb (used without object)
6. to arouse pique in someone: an action that piqued when it was meant to soothe.
verb (used without object)
14. to project in a peak.
15. to attain a peak of activity, development, popularity, etc.: The artist peaked in the 1950s.
verb (used with object)
16. Nautical . to raise the after end of (a yard, gaff, etc.) to or toward an angle above the horizontal.
From these definitions, you can see that the proper statement would be That short skirt and low-cut top piqued his interest. and NOT That short skirt and low-cut top peaked his interest.
The sentence clearly means that the provocative clothing aroused the man's interest. Further, you can look at the fact that if you used peak here, it would be a transitive verb, because it has the direct object of his interest. (His interest was piqued by the clothes.) But the only definition given of peak as a transitive verb (used with object) is a nautical reference. You can peak the gaff while sailing, which would mean you raised the after end above the horizontal. The other definitions are intransitive usages of peak.
While dictionary.com doesn't list peak as a transitive verb meaning "To bring to a maximum of development, value, or intensity" or "to cause to come to a peak", there are other sources that do. This is where you get people trying to justify the use of peak in sentences like the one above.
They argue that the sexy clothing could have brought the man's interest to a maximum of intensity, or could have caused his interest to come to a peak, and so that sentence could be correct.
But it's not. It sounds ridiculous, and it looks ridiculous. As a reader, I would never assume a writer intended that meaning of peak, and as a writer, I would never construct a sentence that way. If that's truly the intent of the sentence why wouldn't one simply say The short skirt and low-cut top brought his interest to a peak. There's no grey area about meaning there. Although it's still a ridiculous sentence. If some skimpy clothing brings a character's interest to the highest point, I sure hope that character is a 12-year-old boy who gets big thrills from very little.
To be honest, I don't know why some dictionaries list peak as a transitive verb in anything other than the nautical usage. (Dictionary.com doesn't; Oxford doesn't; Merriam-Webster does, but doesn't specify anything about nautical usage; You Dictionary does; American Heritage does.) Perhaps it's an old usage that has fallen out of style? I'm not sure. But it's used so far and between that I couldn't find a single usage of it as a transitive verb after lots of Googling and discussion with word nerds on Facebook and Twitter.
So there you have it. Now you know the proper definition of pique versus peak, and should you ever forget which you want to use, look at whether you're dealing with a transitive or intransitive verb. With the exception of the nautical usage we covered above, you should NOT be using peak as a transitive verb. That should take care of using peak when what you want to use is pique.
And of course, please don't use peek when you mean to use either of the other two. Just don't.
If I ever see any of you write "It peaked my interest", I will call you on it. I might have a temper tantrum about it first, but then I'll call you on it.
That's one of my grammar pet peeves. What are yours?