1.) Someone who says the very first thing that comes to their mind. Just like a lottery machine and how the first number that comes out is the number they say out loud.

2.) It is also when the thing you say is completely random. Like when a lottery machine spits out a number ball at random.
Jason keeps on yelling out completely random things. I think he may have lottery mouth.
by Jizzle99 April 18, 2015
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