Simple house (3)
I believe the answer is:
hut
'simple house' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for hut that I've seen before include "Small shed for storing, say, garden tools" , "Small building or shelter" , "Small structure as for watchman" , "'Shack, hovel (3)'" , "Simple abode" .)