Dad goes in for jogging, determined (9)
I believe the answer is:
diagnosed
'determined' is the definition.
(to diagnose is to determine what something is)
'dad goes in for jogging' is the wordplay.
'for jogging' indicates anagramming the letters (letters get jogged out of place).
'dad'+'goes'+'in'='dadgoesin'
'dadgoesin' with letters rearranged gives 'DIAGNOSED'.
(Other definitions for diagnosed that I've seen before include "Determined" , "Identified disease" .)