Land provided by heiress (4)
I believe the answer is:
eire
'land' is the definition.
(Eire is an example)
'provided by heiress' is the wordplay.
'provided by' indicates a hidden word (the answer is provided within the clue).
'EIRE' is hidden in the letters of 'heiress'.
(Other definitions for eire that I've seen before include "island" , "Southern Ireland" , "Official name of the Irish Republic, 1937-49" , "Land" , "Breakaway state" .)