bellowing

(noun) a very loud utterance (like the sound of an animal). Synonyms: bellow, holla, holler, hollering, hollo, holloa, roar, roaring, yowl. Example: "His bellow filled the hallway."

(verb) shout loudly and without restraint. Synonyms: bawl, bellow.

(verb) make a loud noise, as of animal. Synonyms: bellow, roar. Example: "The bull bellowed."