Turn on a pivot (6)
I believe the answer is:
swivel
'turn on a pivot' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for swivel that I've seen before include "Revolve" , "Connection allowing rotation" , "Turn as if on a pivot, like a kind of chair" , "Turn on a chair, say" , "swinging" .)