Definition of muss up

1 : to batter or handle roughly : beat, maul wanted to get there in time to muss him up a bit— J. F. Fishman
2 : to make chaotic or incoherent : confuse sold them liquor, and generally mussed up the situation— William Kent

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Cite this Entry

“Muss up.” Dictionary, Merriam-Webster, Accessed 14 Aug. 2020.

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