Rotor arm? (8)
I believe the answer is:
revolver
This clue might be a double definition.
'rotor' is the first definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'arm?' is the second definition.
(revolver is a kind of arm)
Can you help me to learn more?
(Other definitions for revolver that I've seen before include "Weapon holding maybe six rounds" , "Pistol - Beatles album" , "1966 platter" , "Type of gun" , "Six-shooter" .)