Conforming part of the body (6)
I believe the answer is:
instep
This might be a double definition.
'conforming part' is the first definition.
'instep' can be an answer for 'part' (instep is a kind of part). I'm unsure of the 'conforming' bit.
'the body' is the second definition.
The definition and answer can be both man-made objects as well as being singular nouns.
Perhaps there's an association between them I don't understand?
'of' acts as a link.
Can you help me to learn more?
(Other definitions for instep that I've seen before include "One part of Oxford" , "downtrodden area" , "Arched part of foot" , "Top of foot" , "Part of foot between toes and ankle" .)