Drunk pinches copper and metal (7)
I believe the answer is:
mercury
'metal' is the definition.
(I know that mercury is a type of metal)
'drunk pinches copper' is the wordplay.
'drunk' becomes 'merry' (merry can mean cheerfully drunk).
'pinches' is an insertion indicator (pinch can mean to steal).
'copper' becomes 'Cu' (Cu is the chemical symbol for copper).
'merry' enclosing 'cu' is 'MERCURY'.
'and' acts as a link.
(Other definitions for mercury that I've seen before include "Metal in thermometer or barometer" , "Lead singer" , "Metal liquid at room temperature" , "one in distant orbit?" , "One associated with Queen" .)