Verb

(en verb)

To utter words, especially complaints or angry expressions, indistinctly or with a low voice and lips partly closed; to say under one's breath.

You could hear the students mutter as they were served sodden spaghetti, yet again, in the cafeteria.

The beggar muttered words of thanks, as passersby dropped coins in his cup.

* {{quote-news

, year=2012 , date=June 28 , author=Jamie Jackson , title=Wimbledon 2012: Lukas Rosol shocked by miracle win over Rafael Nadal , work=the Guardian citation , page= , passage=This set – the set of Rosol's life – was studded with aces and menacing ground-strokes that left Nadal an impotent spectator often muttering to himself and at the umpire regarding a perceived misdemeanour by his opponent.}}

To speak softly and incoherently, or with imperfect articulations.

The asylum inmate muttered some doggerel about chains and pains to himself, over and over.

* Dryden

Meantime your filthy foreigner will stare, / And mutter to himself.

To make a sound with a low, rumbling noise.

April could hear the delivery van's engine muttering in the driveway.

* Alexander Pope

Thick lightnings flash, the muttering thunder rolls.

Verb

(en verb)

(lb) To cry out suddenly, from some strong emotion.

*

*:“Heavens!” exclaimed Nina, “the blue-stocking and the fogy!—and yours are'' pale blue, Eileen!—you’re about as self-conscious as Drina—slumping there with your hair tumbling ''à la Mérode! Oh, it's very picturesque, of course, but a straight spine and good grooming is better.”