"slaving" or "(being) slaved" as an intransitive verb has a history that predates modern computing meaning a mechanical or electromechanical system that takes its control inputs from another (master) source. Examples:

https://www.quora.com/What-is-a-slave-engine-on-on-a-locomot...

https://en.wikipedia.org/wiki/Horizontal_situation_indicator

https://en.wikipedia.org/wiki/Propeller_synchronization