Synonyms for Hollo (same or very similar meaning)
WordNet sense 1 (a very loud utterance (like the sound of an animal)):
bellow, holler, roar, roaring, yowl, bellowing, holla, hollering, holloaWordNet sense 2 (utter a sudden loud cry):
call, cry, scream, shout, squall, yell, shout outFrom the ODE community, based on WordNetadd/edit