Rotate some planetary gears the other way (6)
I believe the answer is:
gyrate
'rotate' is the definition.
(gyrating is a kind of rotating)
'some planetary gears the other way' is the wordplay.
'some' says the answer is hidden in the clue (some of the parts of the word are used).
'the other way' says the letters should be written in reverse.
'etaryg' can be found hidden inside 'planetary gears'.
'etaryg' in reverse letter order is 'GYRATE'.
(Other definitions for gyrate that I've seen before include "Move around in circles, revolve" , "Move quickly in a spiral" , "Move in a spiral course" , "Revolve quickly and repeatedly around one's own axis" , "Move rapidly in a circle" .)