Picked up tin for one character (6)
I believe the answer is:
mettle
'character' is the definition.
(mettle is a kind of character)
'picked up tin for one' is the wordplay.
'picked up' indicates a 'sounds like' (homophone) clue.
'tin for one' becomes 'metal' (tin is a kind of metal).
'metal' sounds like 'METTLE'.
(Other definitions for mettle that I've seen before include "Spirit could sound like iron, say" , "Courage sounds like iron, for instance" , "Temperament; courage" , "Pluck" , "Inherent character - courage" .)