Pieces of land used for races (5)
I believe the answer is:
acres
'pieces of land' is the definition.
'acres' can be an answer for 'land' (synonyms). I'm not certain of the 'pieces of' bit.
'for races' is the wordplay.
'races' anagrams to 'ACRES'.
But, I am not sure how this is indicated.
'used' acts as a link.
Can you help me to learn more?
(Other definitions for acres that I've seen before include "Scare (anag)" , "may burden landed folk" , "Cares about the tracts of land" , "Cares about the land measures" , "Extensive landed property (often rolling)" .)