Verb - when you are growling out a girl and you accidently miss and lick her...well we could sugar coat it and call it her moon, but yes we are talking about her sphincter. This is awkward for both parties, so much so that the giver lets out a growl of disgust in a wolf like fashion.
"I was going down on Penny and it was really dark... and well I kinda missed..." - Dave
"Oh no dude, don't tell me you had to growl at the moon." - Shane