A metaphor for having done something you regret and can't take back. As with too much alcohol, the more Mistake Whiskey you consume, the worse you feel; especially the next day. Coined by J. Jacques in his webcomic Questionable Content.
"I had already drunk three quarters of the bottle of Mistake Whiskey, so I figured I might as well finish the whole thing."
n. a combination of pain in the ass and mistake. sometimes an occurrence is a pain in the ass but was still worth the time and effort involved. a mistake in the ass is not one of these occurrences.
after i got done at work, it took me an hour to drive through rush hour traffic so i could vote before the polls closed. that was sure a mistake in the ass.