Grumble, v. i. [imp. & p. p. Grunbled; p. pr. & vb. n. Grumbling.]
Etymology: [Cf. LG. grummeln, grumman, D. grommelen, grommen, and F. grommeler, of German origin; cf. W. grwm, murmur, grumble, surly. sq. root35. Cf. Grum, Grim.]
1. To murmur or mutter with discontent; to make ill-natured complaints in a low voice and a surly manner. L'Avare, not using half his store, Still grumbles that he has no more. Prior.
2. To growl; to snarl in deep tones; as, a lion grumbling over his prey.
3. To rumble; to make a low, harsh, and heavy sound; to mutter; as, the distant thunder grumbles.
2 other Webster entries under this spelling
Grumble, v. t.
To express or utter with grumbling.
Grumble, n.
1. The noise of one that grumbles.
2. A grumbling, discontented disposition. A bad case of grumble. Mrs. H. H. Jacksn.
Shades of meaning
Fernald has no entry of its own for grumble; he lists it under complain.
He lists it without comment; the entries above explain its neighbors.