Man's man, 1/100 (7)
I believe the answer is:
douglas
'man's' is the definition.
'man 1100' is the wordplay.
I cannot really understand how this works, but
'man' could be 'doug' and 'doug' is present in the answer.
The remaining letters 'las' is a valid word which might be clued in a way I don't see.
This may be the basis of clue (or it may be nonsense).
(Other definitions for douglas that I've seen before include "See 13" , "IOM town" , "Manx capital" , "place of Man" , "Capital of the Isle of Man" .)