A type of girl denim jeans or pants that are especially favorable for showing the perfect curves of a girl's buttocks, usually pocketless. They can only be worn by some.
"Dude, did you see that chick's ass?"
"Yeah, girls should wear ass jeans more often."
That one pair of jeans that makes you look in the mirror and say, "I'd tap that." Also known as the pair of jeans your butt looks best in.
"I went out today and bought a pair of Sevens... I think they might be my new ass jeans."