The sort of insult and illiterate with an IQ of, perhaps, 40 may give to someone who plays a 'brass' instrument (even if it is really a saxophone...). This is, of course, because they cannot begin to comprehend the level of skill it takes to play an instrument so they will come out with this crappy insult in hopes of making the recipient of the insult 'feel bad'. It's used when they know they have lost in all meanings of the word.
"HEAY LUK GUYZ ETS DE BRASS BOY!!1!1!" - your neighborhood illiterate, John.
by Rework January 17, 2018
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