Potato chip seasoning (4)
I believe the answer is:
salt
'potato chip seasoning' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for salt that I've seen before include "dry wit" , "Pile up" , "Crystalline substance for the table" , "Crystalline substance used to season food" , "Mariner; sodium chloride" .)