mostly used by women to refer to a casual sexual partner they can call up for a booty call any time, regardless of her relationship status.
It's no-strings, no-emotions, hardcore sex-only.
Men often use the term fuck buddy for the same thing.
A more gender neutral term might be friends with benefits
Karen: "Damn, another lousy boyfriend history, I think I need to call my recyclable, Rico, to get myself grounded before hunting up a new boyfriend.
A person that recycles
-Hey that guy recycles,huh.
-Yeah his a recyclable