Agony and ecstasy surrounding York's flower (9)
I believe the answer is:
hellebore
'flower' is the definition.
The definition and answer can be both plants as well as being singular nouns.
Maybe there's a link between them I don't understand?
'agony and ecstasy surrounding york's' is the wordplay.
'agony' becomes 'hell' (I can't justify this - if you can you should give a lot more credence to this answer).
'and' means one lot of letters go next to another.
'ecstasy' becomes 'E' (informal term for the drug).
'surrounding' indicates putting letters inside.
'york' becomes 'ebor' (abbreviation for Eboracum, Latin name for York).
'hell'+'e'='helle'
'helle' going around 'ebor' is 'HELLEBORE'.
Can you help me to learn more?
(Other definitions for hellebore that I've seen before include "In bed I grow" , "it comes out at Christmas" , "Flower of the lily family found in rebel hole" , "Winter-flowering plant" , "flowering plant" .)