Synonyms of yammer

1 Syllable
speak, caw, cried, wail, howl, meow, moo, moan, yowl, kvetch, carp, yak, fuss, shout
2 Syllables
nickers, whinny, blah-blah, complain, yapping, whinnies, yapped, beefed, spake, complains, halloo, prattled, shouted, griping, yakked, spoke, yoo-hoo, nicker, grumble, whimper, yakking, gripe
3 Syllables
blathered, bellyache, repine, complained, gibberish
4 Syllables
verbalizing, verbalize, yakkety-yak, verbalized