Father's wise, in a way (7)
I believe the answer is:
passage
'way' is the definition.
(I know that passage is a type of way)
'father's wise' is the wordplay.
'father's' becomes 'pa's' (pa can mean dad or father).
'wise' becomes 'sage' (similar in meaning).
'pas'+'sage'='PASSAGE'
'in a' acts as a link.
(Other definitions for passage that I've seen before include "Book extract; transit" , "crossing" , "Sea/air journey" , "street" , "Alley - corridor" .)