Yield chessman at game's end (5)
I believe the answer is:
spawn
'yield' is the definition.
(I've seen this before)
'chessman at game's end' is the wordplay.
'chessman' becomes 'pawn' (pawn is a kind of chessman).
'at' is a charade indicator (letters next to each other) (I've seen this in other clues).
'game's end' becomes 's' (I am not sure about this - if you are sure you should believe this answer much more).
'pawn' put after 's' is 'SPAWN'.
Can you help me to learn more?
(Other definitions for spawn that I've seen before include "Generate; fish eggs" , "Breed" , "(Of fish) release eggs" , "Give rise to; fish egg" , "Mass of eggs laid in water" .)