A rainjob is the act of having sex outdoors in the rain and using rainwater as lubricant for your penis.
"Dude, i was getting a nice rainjob last night and the rain smelt like shit."
by The Boy That Lost His Horse August 29, 2009
1 more definition
When after receiving a rainbow kiss a woman proceeds to give a blow job with her menstruation still in her mouth
My girl was on the rag last night, but it was cool cause I got a rain job out of it.
by Creme June 27, 2006