Lying for effect; Letting your mouth write checks that your ass can't cash.

when you've done something so cringe you can't stop replaying it in your head and it stops you from getting on with your every day life

Too afraid to run your mouth to someone directly, but once they start to walk away you look down and run your mouth like a pussy. Too scared to run your mouth until the possibility of a real confrontation has died down.

Letting another person know that if they don't stop whatever it is the are doing. Then that person will more than likely die by having a hole in thier neck.