Clubs possibly hosting Frenchmen for conference (6)
I believe the answer is:
summit
'for conference' is the definition.
(as in a political summit)
'clubs possibly hosting frenchmen' is the wordplay.
'clubs possibly' becomes 'suit' (clubs is an example of a card suit. I am not sure about the 'possibly' bit.).
'hosting' is an insertion indicator (inserted letters are welcomed in or hosted).
'frenchmen' becomes 'MM' (two M's - M is short for Monsieur).
'suit' going around 'mm' is 'SUMMIT'.
Can you help me to learn more?
(Other definitions for summit that I've seen before include "Talks" , "important meeting" , "international diplomacy" , "A high-level meeting?" , "Highest point (of hill)" .)