On board, a game fellow (8)
I believe the answer is:
chessman
'on board' is the definition.
The answer and definition can be both man-made objects as well as being singular nouns.
Maybe there's a link between them I don't understand?
'a game fellow' is the wordplay.
'a game' becomes 'chess' (chess game is a kind of game).
'fellow' becomes 'man' (fellow can mean a man).
'chess'+'man'='CHESSMAN'
Can you help me to learn more?
(Other definitions for chessman that I've seen before include "that's played on board" , "Playing piece" , "queen, perhaps" , "Eg, bishop, knight" , "Eg, bishop or rook" .)