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slang To jumble up or ruin something. A noun can be used before or after "up." Boy, you really bollixed up this report—I'm not sure I can even fix it.
bollix something up
Inf. to ruin something; to mess something up. Please don't bollix my stereo up. Who bollixed up the folded laundry?
To make a mess of something because of mistakes or poor judgment: I'm afraid you've bollixed up that job badly! Don't make me paint the chairs; I'll just bollix it up.