Angle of ray? (4)
I believe the answer is:
fish
I believe this clue is a double definition.
'angle' is the first definition.
(I know that angle can be written as fish)
'ray?' is the second definition.
(ray is a kind of fish)
'of' is the link.
(Other definitions for fish that I've seen before include "Aquatic creature(s)" , "Aquatic animal(s)" , "Weatherman" , "Trawler's catch" , "Burbot or turbot, for example" .)