Revolution, turning (8)
I believe the answer is:
rotation
This clue is a double definition.
'revolution' is the first definition.
(I know that revolution can be written as rotation)
'turning' is the second definition.
(I know that rotation is a type of turning)
(Other definitions for rotation that I've seen before include "Recurrent order" , "Turning movement around an axis" , "Cycle - revolution" , "Action of turning" , "Process of turning" .)