Kind of board at a nail salon (5)
I believe the answer is:
emery
'kind of board at a nail salon' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for emery that I've seen before include "Hard grey-black mineral used as an abrasive" , "Abrasive form of corundum" , "Black abrasive" , "Hard black-grey mineral used in grinding and polishing" , "Dick - - , late comedian" .)