Difference between Grumble and Murmur

GRUMBLE vs MURMUR: NOUN

The sound made by any condition which produces noisy, or turbulent, flow of blood through the heart.
Low or indistinct sounds or speech.
A complaint half suppressed, or uttered in a low, muttering voice.
A low, confused, and indistinct sound, like that of running water.
In medicine, any one of various sounds, normal and pathological, heard in auscultation.
A muttered complaint or protest; the expression of dissatisfaction in a low muttering voice; hence, any expression of complaint or discontent.
A low sound continued or continuously repeated, as that of a stream running in a stony channel, of a number of persons talking indistinctly in low tones, and the like; a low and confused or indistinct sound; a hum.
An indistinct, whispered, or confidential complaint; a mutter.
A low, indistinct, continuous sound.
An abnormal sound of the heart; sometimes a sign of abnormal function of the heart valves
A low continuous indistinct sound; often accompanied by movement of the lips without the production of articulate speech
A complaint uttered in a low and indistinct tone
A schwa that is incidental to the pronunciation of a consonant
An abnormal sound, usually emanating from the heart, that sometimes indicates a diseased condition.

To utter in a grumbling fashion.
To complain.
Make complaining remarks or noises under one's breath
Show one's unhappiness or critical attitude
Make a low noise
To utter or emit low dull rumbling sounds
To make a low, growling or rumbling noise, like a hungry stomach or certain animals.

To express in a grumbling discontented manner.
To rumble or growl.
To complain in a surly manner; mutter discontentedly.
To rumble; to make a low, harsh, and heavy sound; to mutter.
To growl; to snarl in deep tones.
To murmur or mutter with discontent; to make ill-natured complaints in a low voice and a surly manner.

To make a low continued noise, like the hum of bees, a stream of water, distant waves, or the wind in a forest.
To utter complaints in a low, half-articulated voice; to feel or express dissatisfaction or discontent; to grumble; -- often with at or against.
To say in a low indistinct voice; utter indistinctly.
To complain in low mumbling tones; grumble.
To make a low, continuous, indistinct sound or succession of sounds.

To make a low continuous noise, like the sound of rushing water or of the wind among trees, or like the hum of bees.
To utter words indistinctly; mutter.
To grumble; complain; utter complaints in a low, muttering voice; hence, in general, to express complaint or discontent: with at or against.
Synonyms To repine, whimper.
To utter indistinctly; say in a low indistinct voice; mutter.
An abnormal sound of the heart
A low continuous indistinct sound

Griping, Moan, Complain, Jones, Gnarl, Grouch, Croak, Rumble, Rumbling, Growl, Murmuring, Scold, Murmur, Muttering, Mutter

Breathe, Breath, Gasp, Coo, Whisper, Murmuration, Murmur vowel, Cardiac murmur, Gnarl, Heart murmur, Croak, Grumble, Grumbling, Muttering, Mutter

Grousing, Whine, Griping, Moan, Jones, Gnarl, Grouch, Rumble, Rumbling, Growl, Murmuring, Scold, Murmur, Muttering, Mutter

Blow, Blast, Blowing, Wind, Breathing, Breathe, Breath, Gasp, Whisper, Gnarl, Heart murmur, Grumble, Grumbling, Muttering, Mutter

Murmur also answered questions I had and helped.
There was a murmur of surprise and awe.
Did ever murmur spring from lips of thine?
The man fell dead without a murmur, watching.
Conservative, but even I am beginning to murmur.
A murmur of protest rippled across the ballroom.
The murmur itself is not treated; the underlying cause of the murmur may or may not be treated.
An echocardiogram is necessary to differentiate between a heart murmur that is just due to excitement versus a heart murmur from underlying heart disease.
The drowsing murmur of the five and twenty studying scholars soothed the soul like the spell that is in the murmur of bees.
On auscultation, the diastolic decrescendo murmur is softer, shorter, and lower pitched than the murmur heard with chronic AR.