IPA: /ˌmɛɡəˈfoʊnɪk/
KK: /mɛgəˈfoʊnɪk/
Describing something that is very loud and echoing, similar to the sound made by a megaphone.
The megaphonic announcement could be heard from blocks away.
Megaphonic → It is formed from "mega-" (from Greek "megas", meaning large or great) and "phonic" (from Greek "phonē", meaning sound). The word "megaphonic" refers to something that produces a large or great sound.
Think of 'mega' meaning large and 'phonic' relating to sound — this helps you remember that megaphonic means producing a large sound.