bullhorn

大聲公、手提擴音器、擴音喇叭美式

The officer shouted instructions to the crowd through a bullhorn.

那名警員用大聲公向人群喊出指示。

用擴音器喊話、大聲宣布少用

The organizers bullhorned the new meeting time to everyone outside.

主辦單位用擴音器向外面的所有人喊出新的集會時間。