1 definition by Stone, Keith

adj. The act of still having your virginity in college while being surrounded by drunken pussy 24/7. Drinking excessively almost everyday for no apparent reason while also going on explicitly long rants about nothing that have no relevance to the pertaining situation. Not showering for days at a time is also a trait of O'Callaghan. In summary, the act of completely embarrassing the Irish race one drunken night at a time.
Guy 1: "Hey man is he a pedophile?"
Guy 2: "No, he is just O'Callaghan!!"
by Stone, Keith September 16, 2010
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