Unidentified substance, especially located on something that should be clean and pristine.

A sharded crystal like substance that ma fucka's been known to smoke.Gakk

The sweaty, often cheesy and displeasing odor/taste that arises from the undercarriage of one's nutsack that is a collection of ball cheese and ass stink. may cause girlfriends to gag or be completely disgusted.

Gakk is the definition of talking to your phone to text, sending the message only to realize it makes no sense at all. Then you have to retype your corrected message over again by hand, explaining it was talk to text and it didn’t send the right message.