God Knows What.
It's said when someone wants to say that anything can happen in a situation. "Looking for sex and GWK with another guy". Because we booked this hotel, GKW is going to happen to us.
by Brasf April 22, 2011
an unidentifiable substance, especially a dangerous one (from god knows what)
The water he drank in the video had GKW in it, as evidenced by his remark about sleeping.
by The Return of Light Joker April 08, 2011