Seeker of reduced fare, not one to get put off (5)
I believe the answer is:
deter
'put off' is the definition.
(thesaurus)
'seeker of reduced fare not one' is the wordplay.
'seeker of reduced fare' becomes 'dieter' (someone aiming to eat less food or fare).
'not' suggests deleting specific letters.
'one' becomes 'i' (Roman numeral).
'dieter' with 'i' taken out is 'DETER'.
'to get' acts as a link.
(Other definitions for deter that I've seen before include "Discourage (someone from an action)" , "Try to prevent" , "Put (someone) off" , "Put off (from an action)" , "Hinder, prevent" .)