in the matter of (used typically as the first word in the heading of an official document or to introduce a reference in a formal letter)

re: invoice 87

the chemical element rhenium

(in tonic sol-fa) the second note of a major scale

the sun god, the supreme Egyptian deity, worshipped as the creator of all life and typically portrayed with a falcon's head bearing the solar disc. From earliest times he was associated with the pharaoh

each of the lines in which light (and heat) may seem to stream from the sun or any luminous body, or pass through a small opening

a ray of sunlight came through the window

a straight line extending indefinitely in one direction from a point

the ray that runs from the centre of the circle to the point of tangency

a thing that is arranged radially

a broad flat marine or freshwater fish with a cartilaginous skeleton, winglike pectoral fins, and a long slender tail. Many rays have venomous spines or electric organs

the chemical element of atomic number 75, a rare silvery-white metal which occurs in trace amounts in ores of molybdenum and other metals

religious education (as a school subject)

(in the UK) Royal Engineers