1. complaints expressed in a bad-tempered way
2. low rumbling sounds

1. to complain in a bad-tempered way
2. to make a low rumbling sound

Examples

• He grumbles about the weather every morning.
• The old man grumbles constantly about young people today.
• Thunder grumbles in the distance during the storm.
• Her stomach grumbles when she’s hungry.
• I’m tired of listening to his grumbles about work.
• The grumbles from the audience showed their dissatisfaction.
• We could hear the grumbles of the approaching thunder.