annunciator
noun /əˈnʌnsieɪtə(r)/
/əˈnʌnsieɪtər/
(physics- a bell, light or other device that shows which of several electrical circuits is in use
信号器：铃，灯或其他设备，显示正在使用的几个电路中的哪个词 词源mid 18th cent.: from late Latin annunciator, from the verb annunciare, variant spelling of annuntiare.