A term popularized by Liz Lemon from 30 rock which is used to describe the event which led to a breakup with someone or something (ie. Brand loyalty)
"What happen, did the relationship suck?"
-Esposito
"Dealbreaker. She wanted to have sex in a Coffin"
-Ryan
(From the TV show castle)

"I loved Microsoft, but Windows Vista was the dealbreaker for me.
by stupidpower December 01, 2009
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A word used to describe the eligibility of a friendship or relationship based on one trait or preference of the other person. Can also be used if you don't agree with someones views.
John: "So whats your least favorite band?"
Jill: " It would have to be Arcade Fire."
John: "Wait...What? You don't like Arcade Fire? Thats a dealbreaker."
OR
Billy: "Favorite Modern Warfare 2 class?"
Johny: "Well, I usually have the UMP .45 with a Silencer, Desert Eagle with a Tac knife, Marathon Pro, Lightweight Pro, and Commando Pro.
Billy: "Woah man. Way to be a noob. We aren't friends anymore, thats a dealbreaker."
by Pandabrother September 08, 2010
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Children. Single folks, you know what I'm talking about.
No, no, you're really sweet, but I didn't know you had six kids. That's a total dealbreaker. Sorry.
by AmbroseKalifornia March 14, 2008
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