Is there something like a Voltage Regulator that will Limit the Voltage so you don't go over a certain Voltage?

The Voltage regulators I've been looking at seem to only work correctly if you put a certain range of voltage into them to get the regulated voltage out.

EX a 12V regulator needs like 13-15 volts in to keep the voltage out at 12v consistently.

I just want something to limit the voltage to no more then 12v max.

EX if I have 3x 3.7 V batterys in series and get an average of 11.1v but they can peak when charged I've read to like 3x 4.2 or more and I don't want to go to high.

I'm guessing there is something out there like this but I don't know what it's called and without the name of it my google searches haven't been very fruitful.

could someone help me out?