Not a word for a win by the way (7)
I believe the answer is:
against
'not a word' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.
'a win by the way' is the wordplay.
'win' becomes 'gain' (synonyms).
'by the way' becomes 'st' (I've seen this in other clues).
'a'+'gain'+'st'='AGAINST'
'for' acts as a link.
Can you help me to learn more?
(Other definitions for against that I've seen before include "In competition with" , "Versus - in contact with" , "In contrast to; touching" , "Opposite to" , "Con" .)