Someone who goes to Vegas, and upon returning, promptly starts mouthing details about the trip. This person is generally the first target of The Vegas Inquisition because they are the lowest hanging fruit.

When confronted about their non-stop yapping, they get very defensive about how they did not divulge every detail.
Jr told Urkel everything that happened on our trip. What a Vegas mouth!
by moraleboatanchor March 21, 2013
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