As referenced in this Meta question, asking about a swear word is absolutely okay (as long as your question meets all the standard criteria, of course); the mere fact that it is a question about a swear word should not bring any opprobrium.
The primary restriction is that you should post in a polite, civil manner, which means that you should not actually use swear words or offensive terms as part of your general presentation.
okay:
What's a more polite way to tell someone to "get the fuck out"?
not okay:
Why the fuck should I have to conform to some anonymous asshole's stupid rules about civility?
Also (as pointed out by @KitZFox in comments), since question titles can automatically be published network-wide in the "hot network questions" sidebar, bowdlerizing the title of your question by character substitution is recommended. I don't know if we have any preferences for "f*ck" vs. "f**k" vs. "f***", but I'd imagine that the more letters you can blank out while still leaving your word recognizable, the more socially acceptable it is.