Power metal put forward (5)
I believe the answer is:
plead
'put forward' is the definition.
(thesaurus)
'power metal' is the wordplay.
'power' becomes 'p' (symbol in physics).
'metal' becomes 'lead' (lead is a kind of metal).
'p'+'lead'='PLEAD'
(Other definitions for plead that I've seen before include "Say one is guilty or not guilty" , "Implore, entreat" , "Beg, implore" , "Sue" , "Beg or petition" .)