Possible Clues:

• Bird embracing artist's attribute
• Essential quality
• Sinatra, Italian, shows mannerism
• Blond hair, e.g
• Characteristic of the flat, by the sound of it
• The tart had a trace of one in it
• It's characteristic and that's flat, by the sound of it
• Having the knack of lifting it: an idiosyncrasy
• Roman nose, e.g.
• Colorblindness, e.g.