Peak is gold following victory (5)
I believe the answer is:
visor
'peak' is the definition.
('visor' can be a synonym of 'peak')
'is gold following victory' is the wordplay.
'gold' becomes 'or' ('or' is the heraldic name for gold).
'following' means one lot of letters go next to another.
'victory' becomes 'v'.
'is'+'or'='isor'
'isor' after 'v' is 'VISOR'.
(Other definitions for visor that I've seen before include "Face-protector" , "Mask" , "Eye protector" , "Eye shield" , "Eyeshade" .)