No longer the point (4)
I believe the answer is:
'no longer' is the definition.
Both the answer and definition are adverbs. Perhaps you can see an association between them that I don't see?
'the point' is the wordplay.
'point' becomes 'n' (N is an example).
Can you help me to learn more?
(Other definitions for then that I've seen before include "Afterwards - as a result" , "Consequently" , "soon?" , "Subsequently - previously" , "At that time; next" .)