A fork of Rural Dictionary
A baby conceived from having sex in a car, usually, but not limited to, the backseat.
Because Ricky and Charlotte have only had sex once, in the back-seat of his car, and she is now pregnant, her child would be considered a Back-Seat Baby.
Term meaning WHORE when there are seven year olds in the room.
"You don't want your identity to be the biggest back seat baby in the school."