Definition of megaphonist in US English:

megaphonist

noun

  • A person who speaks through a megaphone.

Origin

Early 20th century; earliest use found in ‘O. Henry’ (1862–1910), short-story writer (real name William Porter). From megaphone + -ist.

Pronunciation

megaphonist

/ˈmɛɡəfəʊnɪst/