IPA: /ˈbɛloʊər/
KK: /ˈbɛloʊər/
A person who shouts or yells loudly, often in a way that is forceful or angry.
The bellower at the rally drew everyone's attention with his loud voice.
Bellower → It is formed from "bellow" (from Old English "bellan", meaning to roar or cry out) and "-er" (meaning a person who). A bellower is a person who bellows or makes a loud, deep sound.
Think of someone who 'roars' ('bellow') — the '-er' just means a person. A bellower is someone who makes a loud noise.