mess up

Short definition from Wiktionary

Verb

1. 1
   To make a mess of; to untidy, disorder, soil, or muss.
2. 2
   To cause a problem with; to introduce an error or mistake in; to make muddled or confused; spoil; ruin.
3. 3
   To botch, bungle; to perform poorly on.
4. 4
   To make a mistake; to do something incorrectly; to perform poorly.
5. 5
   To cause (another person) to make unwanted mistakes in a given task, usually through distraction or obnoxious behavior.
6. 6
   To damage; injure.
7. 7
   To manhandle; beat up; rough up.
8. 8
   To discombobulate, utterly confuse, or confound psychologically; to throw into a state of mental disarray.

Noun

1. 1
   A mistake or fiasco; something that has gone wrong.
2. 2
   A person who makes many mistakes.