Definition
To complain about something in a low, unhappy voice, often without expecting things to change.
Example
She grumbled about the cold weather all morning.
Show translation
She complained quietly about the cold weather all morning.
Etymology
From early Modern English *grumble* (16th century), likely derived from Middle Dutch *grommelen* or Low German *grummeln*, both meaning "to mutter or rumble." Related to the imitative root that also gives us *groan* and *grunt* — all words that echo the physical sound of dissatisfaction.
Cultural note
Grumbling is so associated with British character that it has become a gentle national stereotype — the "loveable grumbler" is a stock figure in British comedy and literature. In American English the word carries the same meaning but is perhaps slightly more informal; *gripe* or *groan* are close cousins. Note: *grumble* implies low-level, habitual discontent rather than serious anger — calling someone a "grumbler" is more affectionate than insulting.