A French stream in south-west describing new term average (9)
![Ross](/clue/static/ross-mug.min.png)
I believe the answer is:
unextreme
'average' is the definition.
Both the definition and answer are adjectives.
Maybe you can see an association between them that I can't see?
'a french stream in south-west describing new term' is the wordplay.
'a french' becomes 'une' ('a' in French).
'stream in south west' becomes 'xe' (I can't explain this - if you can you should believe this answer much more).
'describing' means one lot of letters goes inside another (describe can mean to form the outline of).
'new' indicates anagramming the letters.
'term' is an anagram of 'trem'.
'xe' enclosing 'trem' is 'xtreme'.
'une'+'xtreme'='UNEXTREME'
Can you help me to learn more?