(2) A person who talks too much, to the point of ad nauseum.
(3) It is also a 30 minute cartoon created in the 1970s by Hanna Barbera. It used to be part of the Saturday morning cartoons. It was created with a format and writing that was similar to that of Scooby-Doo and Josie and the Pussycats.
(1) "You are such a jabberjaw; i can hardly get a word in edgewise."
(2) "Hey jabberjaw. Shut up! I'm trying to tell you something."
(3) "Do you remember that cartoon Jabberjaw? It's being replayed on the Cartoon Network now."
An individual at any social gathering who, typically due to being under the influence of a controlled stimulant (ie: cocaine, amphetamine, adderall, etc.), absolutely refuses to stop talking, interrupting others, or any other general form of jabbering.
"Oh no, everyone duck, I'm pretty sure that fucking Jabberjaw is zeroing in on us."