Area of the back door? (4)
I believe the answer is:
rood
'area' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps you can see an association between them that I don't see?
'back door?' is the wordplay.
'back' shows that the letters should be reversed in order.
'door' in reverse letter order is 'ROOD'.
'of the' is the link.
Can you help me to learn more?
(Other definitions for rood that I've seen before include "Pole, perch or crucifix" , "old piece of land" , "- Loft; - screen" , "Crucifix in church; one quarter of an acre" , "Crucifix on door" .)