rotary switch

rotary switch (plural rotary switches)

1. (electrical engineering) A switch that is operated by turning a knob.
   • 1961 October, “More programme machines for L.T. Northern line”, in Trains Illustrated, page 625, photo caption:

     A close-up of the very compact desk unit for control of the East Finchley programme machine from Leicester Square; the rotary switches at the top are used to set up the train number of any service to be added or cancelled.

• “rotary switch”, in Lexico, Dictionary.com; Oxford University Press, 2019–2022.