A governor is a device that automatically controls adjust or governs, say engine RPM. It is a feedback device that automatically makes adjustments. I used a lawn mover because it is a simple, but great example, a portable generator, or a gas operated pressure washer also would be a great examples. These machines has governers to adjust/maintane engine RPM as load increase.
When you fire up your lawn mover and move the throttle from "turtle" to "Rabbit" - as in full speed-, it runs at... say 2500-3500 RPM. Ones you ram the lawnmower into a tall patch of grass the mover's engine doesn't die, instead you hear this deep sound and the engine revs up. The governer automaticly gives it more throttle/gas to maintain optimal engine speed. Same thing on a generator, the governor adjusts throttle setting to keep the engine from stalling.
A transmission is not a governor, it is a transmission. In our case a CVT, or Continuously Variable Transmissions.

 

nice, that makes sense