stacked, adj.

1.Having large, attractive breasts. See, for example, the lyrics to Bust a move, released by Young M.C. in 1989:

She thinks you're kinda cute so she winks back
And now you're feeling really firm cos the girl is stacked

2.Of a deck of cards: having been tampered with by the dealer so that he knows the contents of the hands he is about to deal.