Charlie, say, with excellent weapon (7)
I believe the answer is:
assegai
'weapon' is the definition.
(assegai is a kind of weapon)
'charlie say with excellent' is the wordplay.
'charlie' becomes 'ass' (both can mean a foolish person).
'say' becomes 'eg' (both can mean for example).
'with' means one lot of letters go next to another.
'excellent' becomes 'ai' (resembles 'A1', old-fashioned term for excellent).
'ass'+'eg'+'ai'='ASSEGAI'
(Other definitions for assegai that I've seen before include "A Zulu warrior's spear" , "something pointed" , "Sea gas I convert to a Zulu spear" , "African spear" , "Zulu fighting spear" .)