Where a person has a tendancy to 'dig a hole' every time they speak, and continue to do so on a particular subject.
"Everything he said made him sound more and more convincingly gay. He had a serious case of shovel mouth!"
by Muggus November 26, 2003
1 more definition
Expression of discontent in which the bottom lip and jaw slightly protrude and the top curls a bit in an almost Elvis Presley style.
I told her she was going to have to take that business elsewhere and she gave me the shovel mouth.
by D. Dubya July 12, 2015