Farting in someone's face then beating the shit into them or the other way round.
Last night some arsehole started on me in a bar so I grabbed his head farted in his eye then beat the shit into the prick now I bet his got a serous Rainbow Face.
by Crusty Clunge June 15, 2014
1 more definition
When eating out a girl, she has her period right in your face.
Dave got a rainbow face from Lauren.
by StONY June 10, 2003