Dictionary.net

• An interrupter in which contact is broken by the movement of an automatically vibrating hammer between a contact piece and an electromagnet, or of a rapidly moving piece mechanically driven.

2010 - New Age Dictionary Database
By Oddity Software

• An interrupter in which contact is broken by the movement of an automatically vibrating hammer between a contact piece and an electromagnet, or of a rapidly moving piece mechanically driven.

1913 - Webster's Revised Unabridged Dictionary
By Noah Webster.