What “regulated” usually means that the lower modes are not achieved with PWM (rapid on/off) which is less efficient than reducing the peak current to the emitter.
“Regulated” can mean a lot of different things, but I think at the very least it means “not direct drive”
I don’t think it specifically relates to PWN, but a good one can.
Correct me if I'm wrong, but the MiniMag Pro is regulated, just not constant current. I think the design is specifically declining current to prolong run-time.