...a green moderate for public attention (9)
I believe the answer is:
limelight
'public attention' is the definition.
(I've seen this before)
'a green moderate' is the wordplay.
'a green' becomes 'lime' (lime is a shade of green).
'moderate' becomes 'light' (I can't justify this - if you can you should give a lot more credence to this answer).
'lime'+'light'='LIMELIGHT'
'for' is the link.
Can you help me to learn more?
(Other definitions for limelight that I've seen before include "Celebrity" , "A theatrical glower" , "Public notice" , "having prominence on stage" , "The illumination on stages, or intense publicity" .)