- Distant traffic noise - Hum - Low, indistinct sound - Mutter in discontent - Quietly spoken utterance - Speak quietly - A low, confused, and indistinct sound, like that of
running water.
- After middle age, abdominal gurgling sound leads to bellyache - expression of discontent - Moan - Mutter in discontent - To murmur or mutter with discontent; to make
ill-natured complaints in a low voice and a surly manner. - To growl; to snarl in deep tones; as, a lion grumbling
over his prey. - To rumble; to make a low, harsh, and heavy sound; to
mutter; as, the distant thunder grumbles.