1. What a comeback can mean a few things. I would say that the main usage and main definition is to go from way behind in a race (or something else), a game, even life to the place where that person is far FAR ahead of where they started from in the game, life, etc...

2. What a comeback can also be said when someone else is slamming or dissen another person, and the person comes back with a witty, smart, hard slammen comeback that tops the other person's cut down so badly that they are put to shame. Sometimes you get to watch a fight after you can say: Man! what a comeback! It aggravates the person who got slammed by the comeback.
1. Did you see the game last night?!?!? The Lions were behind 11 points in the 2nd Quarter, and then what a comeback, they tied up the score, in the 3rd Quarter - it was like they weren't the Lions anymore. I dont know what set fire to their pants; but they got a move on.

2. Person #1 - Yo' Momma so fat that when she farts in a pool they name the Hurricane!

Person #2 - Yeah, well yo Momma so fat that when she stands up the earth tilts on it's axis!

Watcher #1 - Whoa! what a comback! Hahahaha!

Person #1 to watcher #1 - "STFU'! (then he scowls at him).
by IrishDaddy2U April 14, 2010
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