Appealing not to lose amount (7)
I believe the answer is:
winsome
'appealing' is the definition.
(thesaurus)
'not to lose amount' is the wordplay.
'not to lose' becomes 'win' ('win' is the opposite to 'lose').
'amount' becomes 'some'.
'win'+'some'='WINSOME'
(Other definitions for winsome that I've seen before include "Charming (in a childlike way?)" , "Attractive and appealing" , "Captivating" , "Charming, engaging" , "Holding an appeal" .)