Swindle man on board (4)
I believe the answer is:
rook
I believe this clue is a double definition.
'swindle' is the first definition.
(I know that swindle can be written as rook)
'man on board' is the second definition.
(man can mean a chess piece)
(Other definitions for rook that I've seen before include "Ringing in the ears" , "Rank - and - file man" , "Gregarious black bird" , "Fleece - bird" , "A bird; overcharge" .)