Fellow left at home with gold coin (6)
I believe the answer is:
florin
'coin' is the definition.
(historical type of coin)
'fellow left at home with gold' is the wordplay.
'fellow' becomes 'f' (abbreviation - of a society etc.).
'left' becomes 'l' (common abbreviation).
'at home' becomes 'in' ('I'm in' can mean 'I'm at home').
'with' says to put letters next to each other.
'gold' becomes 'or' ('or' is the heraldic name for gold).
'in' put after 'or' is 'orin'.
'f'+'l'+'orin'='FLORIN'
(Other definitions for florin that I've seen before include "Former British silver coin" , "[SHILLINGS] ?" , "An old two-shilling coin" , "Former two shilling coin" , "Two bob, in old money" .)