Right time of life for passion (4)
I believe the answer is:
rage
'passion' is the definition.
(thesaurus)
'right time of life' is the wordplay.
'right' becomes 'r' (common abbreviation).
'time of life' becomes 'age' (age is a kind of time of life).
'r'+'age'='RAGE'
'for' acts as a link.
(Other definitions for rage that I've seen before include "a poetic response to dying light?" , "See red" , "Uncontrollable anger" , "Terrible temper" , "Fierce anger" .)