Bluish-grey bench one removed from row (6)
I believe the answer is:
pewter
'bluish-grey' is the definition.
'bench one removed from row' is the wordplay.
'bench' becomes 'pew' (pew is a kind of bench).
'one' becomes 'i' (Roman numeral).
'removed from' suggests deleting specific letters.
'row' becomes 'tier' (tier is a kind of row).
'tier' with 'i' taken out is 'ter'.
'pew'+'ter'='PEWTER'
(Other definitions for pewter that I've seen before include "Bluish-grey alloy" , "Alloy of tin and lead, often in beer mug" , "prize-money" , "Plate" , "Grey alloy of tin and lead, often in mug" .)