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The lower mouth, which does most of the talking after the upper mouth is fed too many gas-inducing foods.
Woops, there goes old round mouth talking up a storm again. (cabbage rolls last night).
by Tom Simon December 01, 2006
The shape your mouth makes when it's go a cock in it; a cock sucker. A phrase commonly heard on the Bubba the Love Sponge Show - Sirius satellite radio on Howard 101.
That guy was such a jerk that he should be a candidate for round mouth of the day.

Hey man, why are you trying to fag me out all the time. You're such a round mouth.
by Roundy February 22, 2008
a male that gives oral sex to other men.homosexual,fag
They are bunch of roundmouths
by aks March 20, 2004
A cock sucker
Look at that fuckin round mouth
by PorkChopSandwiches February 28, 2008
A description of feminine facial features or expressions on a man.
Hey do you know Joe? He didn't get that round mouth from eating square meals.
by Mr. Moo Bovine August 19, 2007
noun. Term used to describe a person who sucks dick. Describes the shape of their mouth while sucking dick.
Look at Joe kissing the bosses ass.
Yeah.....he's such a round mouth.
by The Ultimate Ranger February 07, 2009
a homosexual
That guy Roger is a real round mouth.
by skettyjoe November 14, 2013