To make oneself scarce for a indefinite period of time on a night out with friends in order to ingest cocaine or other such narcotics that are found in powder form, and thus, requiring privacy and isolation.
"Where's Minky gone, it's his turn to by a round of drinks. Oh he's gone to feed the cat, he'll be munted when he gets back."
By Jean
Feeding The Cats
What you say on the phoneto let the other person know that you can no longer talk freely because someone has entered the room.
Jamie "So what did you do last night?"
Erica "I'm feeding the cats"
Jamie "OK, tell me later."