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1 definition by Chem Eng Milne

 
1.
OMA
Acronym for "One Man Army". Examples in pop culture include the song OMA by Grand Theft Bus, a Canadian, East Coast 'Indy Rock' band.
I wouldn't want to run into that guy in an alley. He looks like an OMA.
by Chem Eng Milne June 11, 2008