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1.
A female who does not have sex without a proir agreement on a steady relationship.

The direct opposite of a Holla back girl.
Man 1: What happened to the that hottie you hooked up with?
Man 2: Haven't talked to her. Turns out she's a Steady McBetty.
Man 1: Don't lock yourself in for ass.
Man 2: Word.
by Johnny Walker Black77 August 26, 2009