saddlebag

noun

1. a large bag or pouch, usually one of a pair, hung from a saddle, laid over the back of a horse behind the saddle, or mounted over the rear wheel of a bicycle or motorcycle.
2. Often saddlebags. excess fat around the hips and buttocks.

noun

1. a pouch or small bag attached to the saddle of a horse, bicycle, etc
2. (plural) informal rolls of fat protruding from the sides of a person’s thighs

n.also saddle-bag, 1774, from saddle (n.) + bag (n.).