crum something up

crum up

slang To ruin something. A noun or pronoun can be used between "crum" and "up." You crummed up this report so much that I can't even fix it!See also: crum, up

crum something up

and crumb something up tv. to mess something up; to louse something up. (See comments at crumb.) Now, don’t crum up this deal. See also: crum, something, up