muck_up
1. [ verb ] make a mess of, destroy or ruin
Synonyms: louse_up fuck_up spoil flub foul_up blunder mess_up ball_up mishandle muff bungle blow fumble bollix bollocks_up bobble fluff bollix_up bollocks screw_up botch_up bumble botch
Examples:

"I botched the dinner and we had to eat out" "the pianist screwed up the difficult passage in the second movement"

Related terms: fail blurt_out blunder spoil bungler fluff ballup screwup
2. [ verb ] soil with mud, muck, or mire
Synonyms: muck mud mire
Examples:

"The child mucked up his shirt while playing ball in the garden"

Related terms: dirty mud
Similar spelling:   mug_up
  mock_up
  muckheap