Occasion on which something is seen (8)

I believe the answer is:
sighting
(Other definitions for sighting that I've seen before include "Managing to see" , "view" , "Catching glimpse of" , "observation" , "Managing to observe briefly" .)
I believe the answer is:
sighting
(Other definitions for sighting that I've seen before include "Managing to see" , "view" , "Catching glimpse of" , "observation" , "Managing to observe briefly" .)