a girl with a nice ass who upon getting married or becoming involved in a relationship with a man finds that the size of her ass begins to multiply in a rate that corresponds with the period of the relationship. (Similar to the way rabbits multiply when they "couple.")
Peter: That Jane used to be hot, but since she hooked up with Mike, damn her ass has got huuge!
Freddy: She's a rabbit-ass. Since she's been with him, her ass is multiplyin' in size every week!
Attempting a task that has been dumped on you by somebody who expects a miracle. Like your dumbass boss who left two hours ago and wants you to get something done in an hour that would have taken him all day to finish. A takeoff on "Hey Rocky, watch me pull a rabbit out of my hat!" from the Rocky and Bullwinkle cartoons.
'The boss expects me to get all these reports done for the corporate office by tomorrow morning, I don't think I'm gonna make it.' 'Well, you know how Steve is about that. He bails and now you have to say "Hey Rocky, watch me pull a rabbit out of my ass!" just like the other days of the week where he is working 27/4'
--OR--
Rick left early again, now I gotta pull a rabbit out of my ass to get this computer fixed.