1 definition by macsd

A sexual act, usually involving a man and a woman.

The man engages in intercourse from behind (vaginally), and sticks his thumb up the woman's ass. The woman usually lets out a cry at this point, and the man sticks his thumb in her mouth to silence or pacify her.
"She was crying a lot, so I bad baby-ed her."
by macsd February 17, 2010
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