A flatulation that is audible only from within the body (intestine).  It is a fart with somewhat of a muffled sound; it is similar to the sound of farting into a peice of pvc.
Verb:  I just grawliffed in my pants.
Noun: I had a grawliff on your mother's head.
Adj: That sounded grawliffy.
Noun: I had a grawliff on your mother's head.
Adj: That sounded grawliffy.
by Trey Cook March 2, 2007
 Get the Grawliffmug.
Get the Grawliffmug.