Some likeness of a man (3)
I believe the answer is:
ken
'a man' is the definition.
(short for Kenneth)
'some likeness of' is the wordplay.
'some' indicates a hidden word (some of the parts of the word are used).
'KEN' is hidden within 'likeness of'.
(Other definitions for ken that I've seen before include "Awareness" , "Know; man's name" , "Understanding - boy's name" , "Identify; -- Livingstone" , "One's range of knowledge" .)