Title aspirant makes rep alter offer (9)
I believe the answer is:
pretender
'title aspirant' is the definition.
'pretender' can be an answer for 'aspirant' (thesaurus). I'm not sure about the 'title' bit.
'rep alter offer' is the wordplay.
'alter' is an anagram indicator.
'offer' becomes 'tender' (tender can mean to offer something).
'rep' anagrammed gives 'pre'.
'pre'+'tender'='PRETENDER'
'makes' is the link.
Can you help me to learn more?
(Other definitions for pretender that I've seen before include "One acting" , "One claiming a title" , "Claimant, like Bonnie Prince Charlie" , "One who claims a title or position" , "fake" .)