Cain's dad (4)
I believe the answer is:
adam
'cain's dad' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for adam that I've seen before include "who transformed the Palladian style?" , "First person" , "Faith, for example" , "- - Bede by George Eliot" , "Eden man" .)