Wasteful background actor versus precious metal worker (11)
I believe the answer is:
extravagant
'wasteful' is the definition.
(similar in meaning)
'background actor versus precious metal worker' is the wordplay.
'background actor' becomes 'extra' (I've seen this in another clue).
'versus' becomes 'v'.
'precious metal' becomes 'Ag' (Ag is the chemical symbol for silver).
'worker' becomes 'ant' (worker is a type of ant).
'extra'+'v'+'ag'+'ant'='EXTRAVAGANT'
(Other definitions for extravagant that I've seen before include "without restraint" , "Freely-spending" , "splashing money around!" , "Exceeding a reasonable level" , "Recklessly wasteful" .)