Fake cocktail/drink. The word exists purely as a way of cracking a joke at a barperson's expense whilst your mates are standing round, thus guaranteeing you kudos for the rest of the evening.
For best effect, order a few normal drinks, then finish off by requesting a matabooboo.
The word originates from Yogi Bear's sidekick. See example for full usage and relevance details.
Donna: "Who's next?"
Wes: "Yeah, can I have 3 pints of Stella, two double vodka red bulls, a sex on the beach and a matabooboo".
Donna: "A what?"
Wes: "A matabooboo"
Donna: "What's a matabooboo"
Wes: "Nothing Yogi, what's the matter with you?"
Donna: "... knob."
A person who thrives on negativity. Somebody who never manages to say anything positive but can waffle on for five hours about the negative side of anything.
Commonly observed in disgruntled employees.
Prit: "Hey, Adie, we've got a 10% pay rise this year"
Adie: "That's rubbish - I wanted 15%. And a bonus. And a car parking space. And another laptop. This place is crap"
Prit: "Shut up Adie, you're such a neg ferret"