A woman's breast to hip ratio. Bust, Waist, and Hips measurements. Often plump women claim to be curvy, but their curves are hidden under a layer of fat so really can't tell if they have curves or not.
When a woman says she has nice curves, it really means that she is fat and has an attitude about it. She may act proud, but deep down inside she is self-conscious and attempts to mask her true feelings with misplaced pride.
Tina says she has nice curves, but she just looks like a cow to me.