Polish expert (4)

I believe the answer is:

buff

This clue is a double definition.

'polish' is the first definition.
(I know that buff is a kind of polish)

'expert?' is the second definition.
(buff can mean an expert or aficionado)

(Other definitions for buff that I've seen before include "fan of > nudism?" , "light shade" , "Polish - fan" , "with attractively well-developed muscles" , "Informal enthusiast - polish him" .)

I've seen this clue in The Mirror, The Telegraph, the Evening Standard and The Everyman puzzle in The Observer.

Want a hint initially instead of a full solution? Install my app