Definition of "bullhorn"

Iʼll press the trigger, and with a loud squeal of ear-piercing feedback, the bullhorn buzzes to staticky life.

2015, Paul Beatty, The Sellout, Oneworld Publications (2016), page 59

[Mark Zuckerberg] didn’t found Facebook to manipulate elections; Jack Dorsey and the other Twitter founders didn’t intend to give Donald Trump a digital bullhorn.

2018 July 1, Katrina Brooker, ““I Was Devastated”: The Man Who Created the World Wide Web Has Some Regrets”, in Vanity Fair‎

CNews, the news network created by the billionaire Vincent Bolloré, topped the ratings in May by giving a new bullhorn for right-wing views on crime, immigration, climate and Covid.

2021 September 14, Norimitsu Onishi, “A Fox-Style News Network Rides a Wave of Discontent in France”, in The New York Times‎