Correct revolver nomenclature

[Tri-Cities Bob]

I have been an NRA Certified Instructor for several decades and this question had never come up before. In a recent class a student asked me for the correct name for the chamber alignment slots located on the cylinder of revolvers. I have since researched the topic and haven't found a good answer. One source refered to these slots as "indents", but that doesn't seem to be the correct terminology. These slots are clearly shown in every nomenclature diagram I have seen, yet they never seem to be identified. For clarification, the slots I am talking about are located on the cylinder and when the cylinder rotates the bolt rises from the bottom of the frame and engages the appropriate slot, assuring that the alignment between the selected chamber and the barrel is correct.

Can anyone out there tell me if there is a correct term to identify these slots/indent? Thanks for your assistance.

[Mike]

Cylinder stop notch.

[Murgatroy]

Cylinder stop notch.

Ditto.

[Tri-Cities Bob]

Thanks for the correct term. Now I can pass it on to all those eager minds.