Nouns

(n)boom, roar, roaring, thundera deep prolonged loud noise
(n)bellow, bellowing, holla, holler, hollering, hollo, holloa, roar, roaring, yowla very loud utterance (like the sound of an animal)“his bellow filled the hallway”

Adjectives

(s)booming, flourishing, palmy, prospering, prosperous, roaring, thriving, burgeoningvery lively and profitable“flourishing businesses”, “a palmy time for stockbrokers”, “a prosperous new business”, “doing a roaring trade”, “a thriving tourist center”, “did a thriving business in orchids”, “the burgeoning administration”, “the burgeoning population”

Adverbs

(r)roaringextremely (of drunkness)“roaring drunk”