A portable loudspeaker with built-in microphone and amplifier(noun)
WordNet. Princeton University. 2010.
Use "loud-hailer" in a sentence
"Seems to me that wandering around empty streets shouting through a loud-hailer might be an offence in itself. on May 13, 2009 at 12: 23 pm TheCogitator"
"Foot Village are four LA hipsters who batter the bejesus out of their drums and scream into a loud-hailer – best in small doses, probably, but invigorating nonetheless."
"Jack spun and saw Mao Gongli standing at the rim of crater beside a huge Type-90 main battle tank, holding a loud-hailer to his mouth."