Plant isn't opiate, sadly (10)
I believe the answer is:
poinsettia
'plant' is the definition.
The answer is an example.
'isn't opiate sadly' is the wordplay.
'sadly' indicates anagramming the letters.
'isnt'+'opiate'='isntopiate'
'isntopiate' anagrammed gives 'POINSETTIA'.
(Other definitions for poinsettia that I've seen before include "bloom" , "American plant" , "poisonous bush" , "Shrub often given at Christmas" , "Ornamental house plant" .)