Here in board meeting a knight starts to stiffen (4)
I believe the answer is:
bone
'stiffen' is the definition.
The definition and answer can be both related to change as well as being verbs in their base form.
Perhaps there's an association between them I don't understand?
'here in board meeting a knight starts' is the wordplay.
'here in board' becomes 'one' (I can't explain this - if you can you should believe this answer much more).
'meeting' means one lot of letters go next to another.
'a knight' becomes 'bt'.
'starts' means to remove the last letter.
'bt' with its last letter taken off is 'b'.
'one' put after 'b' is 'BONE'.
'to' is the link.
Can you help me to learn more?
(Other definitions for bone that I've seen before include "Possibly hammer" , "Eg, rib" , "Ossified material" , "Eg, radius or stirrup" , "Skeleton material" .)