bellowing vs holloa

bellowing and holloa both are nouns.

Word	Noun	Adjective	Verb	Adverb
bellowing	Yes	No	No	No
holloa	Yes	No	No	No

As nouns, bellowing and holloa are synonyms defined as:

bellowing and holloa: a very loud utterance (like the sound of an animal)

Other synonyms of bellowing include bellow, holla, holler, hollering, hollo, roar, roaring, yowl.

bellowing (noun)	holloa (noun)
a very loud utterance (like the sound of an animal)	a very loud utterance (like the sound of an animal)