Possible Clues:

• Bravery? Don't you believe it
• Always brave? Certainly not
• Definitely not (sl.)
• Very clear Five ac in last part of solution of Listener
• Emphatic expression of refusal
• Certainly not what one cured of phobia has
• Not likely to be seen in dreadnought
• Informally, certainly not., who's afraid
• Far one (anag.)
• Certainly not!