megaphone; bullhorn; loudhailer
A handheld or mounted device for amplifying the voice, used in crowds, events, or emergencies.
警察官が拡声器で避難を呼びかけた。
The police officer called for evacuation using a megaphone.
デモ隊は拡声器を使ってスローガンを叫んだ。
The demonstrators shouted slogans using bullhorns.
拡声器 is the general, formal term for any voice-amplifying device (handheld or fixed), while メガホン specifically refers to the cone-shaped handheld type.
拡声器 refers to a loudspeaker used for public announcements or amplifying voice outdoors, while スピーカー is the general term for any sound-output device, including home audio equipment.
Standard kanji spelling; high priority.
Variant spelling using 機 (machine); less common than 拡声器.
Compound of 拡声 (voice amplification) + 器 (device). The kanji 拡 means 'expand', 声 means 'voice', and 器 means 'instrument'.