The term "master switch" typically refers to a device or control mechanism that has the ability to turn multiple devices on or off simultaneously. Synonyms for the term include "kill switch," "main switch," "power switch," "control switch," "shut-off valve," and "emergency stop button." Each of these terms indicates a means of control and regulation of power or flow, and can be used interchangeably with "master switch" in various contexts. Whether used in a technical or practical setting, these synonyms convey the importance of having a centralized means of power control in managing complex systems.