Does one attach handle to door? (9)
I believe the answer is:
nameplate
'does one attach' is the definition.
I can't judge whether this defines the answer.
'handle to door?' is the wordplay.
'handle' becomes 'name' (handle can mean a name or nickname).
'to door?' becomes 'plate' (I can't justify this - if you can you should give a lot more credence to this answer).
'name'+'plate'='NAMEPLATE'
Can you help me to learn more?
(Other definitions for nameplate that I've seen before include "Notice telling who is the occupant" , "One identifies" , "for handle at entrance" , "Plaque" , "It may be attached to an office door" .)