An electronic motor starting circuit where less than full voltage is applied to the motor during starting.
Some electronic switches will ramp the current up over a small time (often less than a second) when you switch on. This greatly helps to reduce wear and tear on motors and particularly gearboxes. Some ESCs also claim this feature though it only really does anything if you slam the throttle wide open from zero.
A feature that limits the start up switching currents of a switching power supply, causing the output voltage to rise gradually to its specified level.