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when a girl is ill'n for the penic, she is penicillin
when a girl really needs a penis in her mouth or vag, she is penicillin.
by tahoenyer January 02, 2012
something you give a girl when you like her, but she doesn't like you.
"I gave her penicillin, and she said we could be more than friends!"
by satya November 17, 2004