1 definition by NomadJr

one who is a sneaky a-hole & hard to spot before it's too late, yet considerably annoying on every level that no one wants to be around...usually due to them just being an idiot & not being able to help their own stupidity..
"That guy who showed up at the last minute to go out with the rest of us is such a buttninja!...we HAVE to ditch him!!
by NomadJr November 4, 2010
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