bollix up

verb

To harm irreparably through inept handling; make a mess: ball up, blunder, boggle, botch, bungle, foul up, fumble, gum up, mess up, mishandle, mismanage, muddle, muff, spoil. Informal muck up. Slang blow, goof up, louse up, screw up, snafu. Idioms: make a muck of. See correct/incorrect, help/harm/harmless.

The verb has one meaning:

Meaning #1: make a mess of, destroy or ruin
  Synonyms: botch, bumble, fumble, botch up, muff, blow, flub, screw up, ball up, spoil, muck up, bungle, fluff, bollix, bollocks, bollocks up, bobble, mishandle, louse up, foul up, mess up, fuck up