A person you only plan to have sex with once. A one-night stand.
He's just a friend but he's cute enough that I would consider a one-off.
by okaytoday April 21, 2006
(n) a one time occurence. An ad-hoc exception to rule. Corporate jargon meaning that you'll do it once and not repeat.
Let's just treat this as a one-off and make sure it doesn't happen again.
by tg28 November 8, 2006
Chiefly British.

1. one of a kind; unique.
2. done, made, or happening only once.
3. a one night stand.
4. something done, made, or happening only once.

This began as a British expression but is now known in the US and elsewhere.
Eddie: Say what?! You base-jumped off the Empire State Building? Were you insane?!

Johnny: Hey, it was only a one-off. I was a turk lad at the time and a little drunk, and I don't think I'd ever have the courage to do it again.
by Raven Grace October 23, 2007
The one-off neon in Jinsoku is so tight, I wonder where he got the idea for that widebody!
by scottyonapotty February 3, 2005
A happening that occurs only once---not repeated---a unique event not seen before
The cheer leader's accepting a date with the chess champion was one-off for her ilk.
by pikeplacemarket June 18, 2009
A quick (often anonymous) one time sexual act with another of the same or opposite sex which ends in climax.
Dude, I can't believe that had a one off with that cop to keep from getting a ticket.

Damn, you really had a one off with that hot soccer MILF behind the beer stand?

by Big NYC Jay June 25, 2008
1. To act quickly without much forethought.

2. To perform a task using as little effort as possible
Person 1: "Did you finish your report?"

Person 2: "Yeah, but I one off'd it. It's a C at best."
by Gamurman November 13, 2011