Wild French caper (7)
I believe the answer is:
frantic
'wild' is the definition.
(similar in meaning)
'french caper' is the wordplay.
'french' becomes 'fr' (abbreviation).
'caper' becomes 'antic' (synonyms).
'fr'+'antic'='FRANTIC'
(Other definitions for frantic that I've seen before include "Wild - frenzied" , "Distraught with fear" , "Frenetic" , "Mad" , "Desperate with worry" .)