Brilliant green space in pitch (9)
I believe the answer is:
sparkling
'brilliant' is the definition.
(thesaurus)
'green space in pitch' is the wordplay.
'green space' becomes 'park' (I have seen 'Public space ' mean 'park' so perhaps 'space' could also mean 'park'. I am not sure about the 'green' bit.).
'in' indicates putting letters inside.
'pitch' becomes 'sling' (I've seen this in another clue).
'park' inserted inside 'sling' is 'SPARKLING'.
Can you help me to learn more?
(Other definitions for sparkling that I've seen before include "Shining with brilliant points of light" , "Not still - like diamonds" , "Effervescent" , "like champagne" , "Fizzy" .)