Chopper blade going up and down (5)
I believe the answer is:
rotor
This could be a double definition.
'chopper blade' is the first definition.
(I've seen this in another clue)
'up and down' is the second definition.
'going' is the link.
This may not be correct. It may belong to one of the definitions.
Can you help me to learn more?
(Other definitions for rotor that I've seen before include "Mechanical turning part" , "Chopper blade" , "Dynamo part" , "one lifting chopper?" , "Revolver" .)