1. past tense of mess; made dirty, untidy, or disorganized
2. past tense of mess; interfered with or tampered with something
Usage: informal
3. past tense of mess; ruined or spoiled something
Usage: informal

Examples

• The kids messed up their room while playing.
• She messed her hair in the wind.
• He messed with the computer settings and broke it.
• Don’t mess with things you don’t understand.
• I messed up the recipe by adding too much salt.
• The rain messed up our picnic plans.
• They messed around in the garage all afternoon.