switcher

noun6

1. •
   One who or that which switches, that is, changes in some way.

   • Switch to Acme brand razors for a closer shave! For a limited time, we'll pay you to be a switcher!
2. •
   One who or that which operates a switch.

   • They all love frugality and conservation; they are manic savers of bits of string and switchers-off of lights. — 1984
3. •
   (US) A railway locomotive used for shunting (switching).
4. •
   (US) The yardman who operates such an engine, or performs a similar role in a trucking depot.
5. •
   A switchmode power supply.
6. •
   Synonym of vision mixer (“device for selecting between video sources”).