1) Expresses utmost concurrence/approval with what your bredrins are saying;
2) Damn straight;
3) You know that/ you know that mother fucking shit;
4) thems the breaks i.e that is just the way it is/ consignment to a sad state of affairs.
Also can be used long form "and aint the the mother fucking truth" or abbreviated to form "ATTMFT"
Dude 1:
"I feel to get drunk tonight"
Dude 2:
"Ain't that the mother fucking truth"
Dude 1:
"ATTMFT, watch"
by Emily Lan November 6, 2006
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