let out vs grumble

Other hyponyms of let out include call, gibber, crow, crow, trumpet, coo, call, cry, holler, hollo, scream, shout, shout out, squall, yell, miaou, miaow, tsk, tut-tut, tut, echo, repeat, call, shoot, gurgle, cry, nasale, bite out, sigh, troat, lift, pant, volley, break into, heave, chorus, splutter, sputter, deliver, hoot, grunt, wolf-whistle, snort, spit, spit out, groan, moan, growl, rumble, howl, wrawl, yammer, yowl, bark, baa, blat, blate, bleat, bellow, roar, cheep, chirp, chirrup, peep, churr, whirr, chirr, meow, mew, quack, hoot, cronk, honk, hiss, sibilate, siss, sizz, sibilate, bray, hee-haw, oink, squeal, clack, click, cluck, low, moo, cackle, gobble, neigh, nicker, whicker, whinny, gargle, caw, mew, haw, hem, croak, cronk, sing, smack, give.