The act of having sex with another person in order to wish said person good fortune. usually done before exams, departures, or future confrontations with someone/something. Plus it rhymes. :)
Rndm Chick: Fuck, I'm totally gonna fail my driving exam tomorrow. Boyfriend: Well I think you'll do fine, but a good luck fuck couldn't hurt right? *5 Minutes Later* Rndm Chick: Im so failing....
by Xero _ Manifest December 29, 2010
Any sexual activity engaged in before a stressful event, such as an exam, performance, work obligation, etc. Often used to release tension, but really just an excuse to get laid.
Before her board exam, I sent her off with a good luck fuck.
by SecretlySexuallyTwisted December 29, 2010