1. An annoying person who keeps showing up
where they are not wanted, who drives people away with

embarrassing lies or inappropriate remarks.

2. Someone who laughs at their own bad jokes.

3. A person who attempts humor by making snide remarks at the wrong times and in serious situations.
"Buckwheat just walked in so its time for us to go.
We'll not waste valuable time listening to that grinwit."
by Phartis March 22, 2011
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