Left with real estate (4)
I believe the answer is:
land
'real estate' is the definition.
(land is a kind of real estate)
'left with' is the wordplay.
'left' becomes 'l' (common abbreviation).
'with' becomes 'and'.
'l'+'and'='LAND'
(Other definitions for land that I've seen before include "German region" , "Capture" , "Gain" , "Ground; country" , "Come down; territory" .)