A stunning treat? (6)
I believe the answer is:
outing
'a stunning treat?' is the definition.
Although both the answer and definition are singular nouns, I cannot understand how they can define each other.
This is all the clue.
Can you help me to learn more?
(Other definitions for outing that I've seen before include "A trip in the open air" , "Jaunt" , "journey" , "Short pleasure trip" , "that puts the private on parade?" .)