Crew from Greenwich on the door (5)
I believe the answer is:
hinge
'greenwich on the door' is the definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Maybe they are linked in a way I don't understand?
'crew from' is the wordplay.
I cannot really understand how this works, but
'from' could be 'in' (I've seen this in other clues) and 'in' is found within the answer.
This may be the basis of clue (or it may be nonsense).
Can you help me to learn more?
(Other definitions for hinge that I've seen before include "Device for letting door etc swing" , "Joint between door and frame" , "Joint on which something swings" , "Fastening for door etc" , "Flexible joint" .)