Noun. (vb. to mumf.)
Muffled shouting; the sound made by someone trying to speak or shout when they have something in or over their mouth (e.g. a gag or a hand). More commonly used in the form "mumfing" than "mumf."

First coined by Lobsterling in a Dirk Gently's Holistic Detective Agency fanfiction on Archive Of Our Own, 9/10/2020.
"With a hand clasped over his mouth, the swearing became a furious mumfing."
"Their words became mumfing for a good few seconds before they realised they could no longer speak."
"Thrashing in zir restraints, ze began to mumf frantically."
by Corvidiss October 23, 2020
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