to choose your friends over your girl/boyfriend.
usually used by a third party... "you should have come to leopolds's birthday party instead of her parent's wife swapping party, mates before dates."

or

"ofcourse i'm coming to leopolds's birthday party, mates before dates, right?"
by Tankman R. December 21, 2007
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When you're mate wants you to fuck their BF/GF and you can't do it cos you have too much self respect and you honor your friendships.
Mate 1: Mate, you should help me fuck Chelsea! She's gaggin for you!
Mate 2: Sorry man, i don't fuck my mates' girlfriends. Mates before dates bud, mates before dates.
by Jeed September 25, 2008
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