Sign, mark (5)
I believe the answer is:
token
This clue is a double definition.
'sign' is the first definition.
(I know that token is a type of sign)
'mark' is the second definition.
(I know that token is a type of mark)
(Other definitions for token that I've seen before include "Sign, symbol or an evidence" , "empty gesture?" , "Symbolic; voucher" , "Something of sentimental value" , "Symbol; metal disc" .)