MUMBLE v. 2 definitions
To speak with the lips partly closed, so as to render the sounds inarticulate and imperfect; to utter words in a grumbling indistinct manner, indicating discontent or displeasure; to mutter. Peace, you mumbling fool. Shak. A wrinkled hag, with age grown double, Picking dry sticks, and mumbling to herself. Otway.…