Male with natural head for cruelty (13)
I believe the answer is:
heartlessness
'for cruelty' is the definition.
(thesaurus)
'male with natural head' is the wordplay.
'male' becomes 'he' (he refers to a man).
'with natural' becomes 'artless' (I've seen this in another clue. I am not sure about the 'with' bit.).
'head' becomes 'ness' (ness is a headland).
'he'+'artless'+'ness'='HEARTLESSNESS'
Can you help me to learn more?
(Other definitions for heartlessness that I've seen before include "Complete lack of sympathy" , "having only three suits in hand, perhaps" , "Cruelty - indifference" , "Unkind condition" .)