look up any word, like ratchet:
 
2.
A term used to describe a sports professional past his/her prime. Most commonly used in association with a washed-up baseball catcher or a previously successful golfer.
"He was such a good catcher, and now he's just an ol' rusty cup."
by Brainiac January 08, 2005
 
1.
A term for a lady's private parts, more commonly used to describe lesbian activities.

See:carpet muncher
Lisa drinks from Amy's rusty cup.
by Ball Jeziorski January 06, 2005