A French game with half of Lyon following is turbulent (6)
I believe the answer is:
unruly
'turbulent' is the definition.
(thesaurus)
'a french game with half of lyon following' is the wordplay.
'a french' becomes 'un' ('a' in French).
'game' becomes 'ru' (rugby union).
'with' is a charade indicator (letters next to each other).
'half of' indicates taking half.
'following' is a charade indicator (letters next to each other).
'lyon' halved is 'ly'.
'un'+'ru'+'ly'='UNRULY'
'is' is the link.
(Other definitions for unruly that I've seen before include "Indisciplined" , "Rowdy" , "Noisy and undisciplined" , "Disposed to disobedience" , "Not disciplined" .)