A phrase used by someone either when someone else doubts they will do something that they are highly likely to do, or they hear someone mention something happening that they really want to happen.

A higher degree of the slang term 'bet'.
Coworker 1: "Did you hear that *unliked coworker* might get fired?"
Coworker 2: "FAT BET."
by ManOfArks October 10, 2019
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a word white people use so they seem cool.
-if u get more than 25 minutes you have to take me to the dome park.

- ok thats a fat bet
by saucyspe May 21, 2017
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term white people to try and fit in with loudon county's language
Bro my parents are going to Florida for the weekend. Dude That's a fat bet.
by utcrash allah October 5, 2016
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