He wined incautiously (5)
I believe the answer is:
edwin
'he wined incautiously' is the definition.
The definition suggests a singular noun which matches the answer.
'he wined incautiously' is the wordplay.
'he' becomes 'ed'.
'wined incautiously' becomes 'win' (I can't justify this - if you can you should believe this answer much more).
'ed'+'win'='EDWIN'
Can you help me to learn more?
(Other definitions for edwin that I've seen before include "Man" , "C7 king of Northumbria" , "- Drood, hero of Dickens' unfinished novel" , "-- Hubble (astronomer)" , "ancient king" .)