Men of many parts perhaps (9)
I believe the answer is:
automaton
'parts perhaps' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
'men of many' is the wordplay.
I cannot quite understand how this works, but
'of' could be 'o' and 'o' is found in the answer.
'many' could be 'm' (Roman numeral for a thousand) and 'm' is located in the answer.
This explanation may well be incorrect...
Can you help me to learn more?
(Other definitions for automaton that I've seen before include "being worked invariably" , "machine" , "Zombie" , "Robotic figure" , "One doesn't think" .)