Meaning: Spoil or ruin
Example: They MESSED UP the discussions and the contract fell through.
Meaning: Make something untidy or dirty
Example: They MESSED UP the room and left stuff all over the place.
Meaning: Cause mental, physical or emotional problems
Example: He took a lot of LSD and it really MESSED him UP.
We have 7 phrasal verbs with 'MESS'