What is Backed Up Woman?
1.
A girl that is involved with another man, she is taken, off the market, unavailable.
John: Hey dude, check that bird out at the bar in the purple dress
Dan: Yer i know mate she is hot
John: I'll see if she wants a drink
Dan: Nahh mate shes a backed up woman (or just backed up)
John: For fucks sake!
See