Piece in hand, last of sixteen (4)
I believe the answer is:
pawn
'piece' is the definition.
(I know that pawn is a type of chess piece)
'hand last of sixteen' is the wordplay.
'hand' becomes 'paw' (synonyms).
'last of' says to take the final letters.
The last letter of 'sixteen' is 'n'.
'paw'+'n'='PAWN'
'in' acts as a link.
(Other definitions for pawn that I've seen before include "Put into hock" , "Chessman often sacrificed" , "a future queen, possibly" , "Hock; cat's-paw" , "Minor chess piece" .)