Yields a chessman on board (6)
I believe the answer is:
spawns
'yields' is the definition.
The definition and answer can be both to do with creating things as well as being verbs in their -s form.
Maybe you can see a link between them that I can't see?
'a chessman on board' is the wordplay.
'a chessman' becomes 'pawn' (pawn is a kind of chessman).
'on' is an insertion indicator.
'board' becomes 'ss' (I can't justify this - if you can you should believe this answer much more).
'pawn' inserted into 'ss' is 'SPAWNS'.
Can you help me to learn more?
(Other definitions for spawns that I've seen before include "Makes large numbers" , "Leads to man" , "Of fish, lays eggs" , "produces offspring" , "Deposits eggs like fish or frogs." .)