Two people behind bishop (5)
I believe the answer is:
brace
'two' is the definition.
(brace is a kind of two)
'people behind bishop' is the wordplay.
'people' becomes 'race' (people can mean a national group or race).
'behind' means one lot of letters go next to another.
'bishop' becomes 'B' (chess abbreviation).
'race' after 'b' is 'BRACE'.
(Other definitions for brace that I've seen before include "Pair - wood-boring tool" , "Stanchion" , "Two of a kind" , "Support or hold steady" , "A pair as of game birds" .)