Copper, say, left after mate juggled (5)
I believe the answer is:
metal
'copper say' is the definition.
(copper is a kind of metal)
'left after mate juggled' is the wordplay.
'left' becomes 'l' (common abbreviation).
'after' says to put letters next to each other.
'juggled' indicates anagramming the letters.
'mate' anagrammed gives 'meta'.
'l' put after 'meta' is 'METAL'.
(Other definitions for metal that I've seen before include "Like steel cutlery" , "Copper or silver, say" , "tin, perhaps" , "Eg, iron, lead" , "lead as one" .)