Mum·ble v. t. [imp. & p. p. Mumbled p. pr. & vb. n. Mumbling ]
1. 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.
2. To chew something gently with closed lips.