mouth off 

to speak out of turn; to backtalk

that bitch has a reputation four mouthing off at the worst possible moments, I should cut her throat before she says any other stuff!

don't mouth off at me, you fuckin prick

mouth off by biancavittoria February 10, 2014

Mouth off 

talk in an unpleasantly loud and boastful or opinionated way.

Here’s a sentence using "mouth off":

She's always mouthing off about how much better she could run the company herself.

Mouth off by Arminkshipper August 5, 2024

Slayer Mouth-off 

When two hardcore metalhead slayer fans argue, possibly for hours, about how much they know about slayer ect. it is a diverse bonding ritual of slayer fans, when they feel threatened by another slayer fan. slayer fans don't usually like other slayer fans.

typical slayer mouth-off..

slayer fan #1: how many slayer tee shirts do you have?
slayer fan #2: 5. how many do you have?
slayer fan #1: 5. how many slayer albums do you have?
slayer fan #2: all of them. how many do you have?
slayer fan #1: all of them including the one that they never actually released. i had to drug Tom Araya to get it..
slayer fan #2: well i have the limited edition slayer action figures!!!
slayer fan #1: how come i'v never seen them in your room?
slayer fan #2: because i hide them under my bed!
slayer fan #1: fuck you man, you just dissed slayer i'm gunna have to kill you.
slayer fan #2: *brutally mutilated* lets put on some slayer.

Slayer Mouth-off by Your Cats On Fire! January 2, 2010

Jerking your mouth off

When all someone does is talk shit and the more they do the more toxic waste comes out.

Guy: I can't stand John Walsh. All he does is talk about fugitives being on the loose! He needs to get a life!

Girl: Quit jerking your mouth off. I can smell the shit when you open it.

Jerking your mouth off by Luna Belle December 11, 2009

pop off at the mouth 

To get carried away in one's speech, usually in regards to talking about someone else or some action one is going to do. Basically talkin' mess taken too far.

After a few too many drinks at the party last night, Joe really started to pop off at the mouth. First he started talking about my physique, then about how he could beat me in a fight.

pop off at the mouth by Dann326 March 4, 2016

running off with the mouth

running off with the mouth one who runs their mouth don't know when to shut up and makes inappropriate comments constantly

always running off with the mouth my ex-girlfriend don't know when to shut up and she makes inappropriate comments constantly

running off with the mouth by littlejimmie December 6, 2019

runs/running off at the mouth 

someone who speaks without the neccessary brain functions required proir to speaking

The fundimentalists are running off at the mouth again with their dribble dick hatered

runs/running off at the mouth by earthlover42 July 10, 2005