kill switch

noun

plural kill switches

: a mechanism or feature on a mechanical or electronic device that allows one or more functions to be turned off or made unavailable

… mobile apps come with a selection of core VPN tools—including a kill switch that will cut your internet connection if the VPN drops. This prevents you from leaking identifiable data while the VPN reconnects, and is particularly important to anyone who uses their mobile to shop online …

—River Hart

… every mile driven came with a human safety monitor on board, sitting ready with a finger on a kill switch to instantly stop the car if necessary.

—Max McDee

—often used figuratively

… his function as the kill switch for departmental waste and mismanagement …

—Travis Durfee

Word History

First Known Use

1948, in the meaning defined above