Basic Swiss cheese Mike cut for the French (9)
I believe the answer is:
elemental
'french' is the definition.
Both the answer and definition are adjectives. Perhaps there's an association between them I don't understand?
'basic swiss cheese mike cut' is the wordplay.
'basic' becomes 'el' (I am not sure about this - if you are sure you should believe this answer much more).
'swiss cheese' becomes 'emmental' (Emmental is an example).
'mike' becomes 'M' (phonetic alphabet: alpha, bravo, charlie etc.).
'cut' is a deletion indicator.
'emmental' with 'm' removed is 'emental'.
'el'+'emental'='ELEMENTAL'
'for the' acts as a link.
(Other definitions for elemental that I've seen before include "Let me lean like forces of nature" , "Basic, primitive" , "Of basic importance" , "Fundamental; supernatural entity" , "Essential" .)