noun the noise of one that grumbles.
2. grumble ·vt to express or utter with grumbling.
3. grumble ·noun a grumbling, discontented disposition.
4. grumble ·vi to growl; to snarl in deep tones; as, a lion grumbling over his prey.
5. grumble ·vi to murmur or mutter with discontent; to make ill-natured complaints in a low voice and a surly manner.
6. grumble ·vi to rumble; to make a low, harsh, and heavy sound; to mutter; as, the distant thunder grumbles.