- To make a mess of; to untidy, disorder, soil, or muss.
- The afternoon breeze messed up my hair.
- To cause a problem with; to introduce an error or mistake in; to make muddled or confused; spoil; ruin.
- The change messed something up, and it's not working anymore.
- To botch, bungle; to perform poorly on.
- Well, I messed up my solo, but otherwise it was a good concert.
- To make a mistake; to do something incorrectly; to perform poorly.
- He has a hard time getting started because he's afraid he'll mess up.
- She messed up on her final exam.
- To cause (another person) to make unwanted mistakes in a given task, usually through distraction or obnoxious behavior.
- Stop bumping me! You keep messing me up!
- To damage; injure.
- He messed up his elbow at the track meet.
- To manhandle; beat up; rough up.
- Her brother's friends messed him up a little after he cheated on her.
- To discombobulate, utterly confuse, or confound psychologically; to throw into a state of mental disarray.
- That girl totally messed me up, man. I'm not sure who I am anymore.
The above text is a snippet from Wiktionary: mess up
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