Scoffed being defeated, losing billions (5)
I believe the answer is:
eaten
'scoffed' is the definition.
(I've seen this before)
'defeated losing billions' is the wordplay.
'defeated' becomes 'beaten' (similar in meaning).
'losing' is a deletion indicator.
'billions' becomes 'b'.
'beaten' with 'b' taken away is 'EATEN'.
'being' is the link.
(Other definitions for eaten that I've seen before include "courses enjoyed?" , "Gobbled" , "having been fed?" , "absorbed in the system" , "Swallowed" .)