grumble
n. countablen. a low, angry sound that someone makes when they are unhappy or complaining. It can also be the act of complaining about something.
n. a low, guttural sound of complaint or dissatisfaction; the act of expressing such discontent. Often used to describe the collective mood of a group or the physical sound of a person.
The crowd let out a loud grumble when the show started late.
There was a constant grumble among the staff about the new office rules and the lack of breaks.
The engine emitted a low, rhythmic grumble as it struggled to maintain power on the steep incline, much to the driver's growing frustration.
Probably from Middle French grommeler, from Old French grumeler (“to murmur, grumble”), from Middle Dutch *grommelen ("to murmur, mutter, grunt"; > Modern Dutch grommelen (“to grumble”)), frequentative of Middle Dutch grommen (“to growl, grunt”). Cognate with Middle Low German grummelen (> Low German grummeln (“to grumble”)), German grummeln (“to grumble”), Norwegian dialectal grymja (“to growl, grunt”).