Mess up

Status: informal

1 : to make a mistake : to do something incorrectly

• About halfway into the recipe, I realized that I had messed up, and I had to start over.

— often followed by on

• She’s afraid she’ll mess up on the test.
• I messed up  on my first attempt.

2 a mess (something) up or mess up (something) : to make mistakes when you are doing or making (something)

2 b mess (something) up or mess up (something) : to make (something) dirty or untidy : to make a mess of (something)

• Don’t mess up my room
• The wind messed up her hair. = Her hair got messed up in the wind.

2 c mess (something) up or mess up (something) : to damage or ruin (something)

• She’s really messed up her life.
• His life has been messed up by his drug addiction.

to damage or change (something) so that it does not work properly

• I don’t know what I did, but I somehow messed up the computer.
• My watch has been messed up[=has not worked properly] ever since I dropped it in the sink.
• The mountains messed up the cell phone signal.

3 a mess (someone) up or mess up (someone) US : to beat and injure (someone)

• He got messed up[=roughed up, beaten up] by a gang of bullies.
• They messed him up pretty badly.

3 b mess (someone) up or mess up (someone) : to make (someone) very upset and unhappy

• Breaking up with her boyfriend has really messed her up.
• She’s been pretty messed up ever since she broke up with her boyfriend.