fatmouth

   ‘I really am disgusted with all of you,’ says a speaker in Catch 22, by Joseph Heller. ‘Okay, fatmouth, out of the car,’ he is told. ‘Fatmouth’ is normally a verb in American slang. It can mean to chatter in a general way or to cajole someone by sweet-talking them. In the above example ‘fatmouth’ appears to mean ‘big-mouth’, one who talks too much and to the annoyance of others.