Shaft (3)
'shaft' is the definition.
(I know that shaft can be written as ray)
This is the entire clue.
(Other definitions for ray that I've seen before include "Shaft, beam" , "A bright beam or flat fish" , "Second note for the flat fish" , "beamer?" , "Pencil of light" .)
(Other definitions for rod that I've seen before include "Stick; angler" , "Baton, pole" , "axle" , "Cane used for flogging" , "that most anglers use" .)