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ray¹

(rā)

a. A narrow stream of radiant energy, especially visible light, traveling in a straight or nearly straight line.

b. A narrow stream of particles such as protons traveling in a straight or nearly straight line.

c. A rapidly moving particle traveling in a straight or nearly straight line.

d. rays Sunshine: Let's go to the beach and catch some rays.

2. A small amount; a trace: not a ray of hope left.

3. Mathematics A straight line extending from a point. Also called half-line.

4. A structure or part having the form of a straight line extending from a point, such as:

a. Any of the bright streaks that are seen radiating from some craters on the moon.

b. A ray flower or the strap-shaped portion of the corolla of a ray flower.

c. A branch of an umbel.

d. One of the bony spines supporting the membrane of a fish's fin.

e. One of the arms of a starfish or other radiate animal.

tr.v. rayed, ray·ing, rays

1. To send out as rays; emit.

2. To supply with rays or radiating lines.

3. To cast rays on; irradiate.

[Middle English rai, from Old French, from Latin radius, pointed stick, spoke, radius of a circle, ray of light (from the representation of rays of light as spearlike shafts), of unknown origin.]

ray²

(rā)

1. Any of various cartilaginous fishes of the superorder Batoidea, having ventral gill slits, enlarged pelvic fins that are fused to the sides of the head, and a flattened body, and including the stingrays, skates, and guitarfishes.

2. Any of various members of this superorder having a whiplike tail usually with a stinging spine, such as a stingray, considered in contrast to a guitarfish, sawfish, or skate.

[Middle English, from Anglo-Norman raie, from Latin raia; possibly akin to Dutch rog and Old English reohhe (both the Latin and the Germanic perhaps ultimately being borrowed from the same European substrate source).]

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ray²

ventral view of a manta ray

Manta birostris

Ray

(rā), John 1627-1705.

English naturalist and theologian who cataloged many plants and animals, wrote works on natural theology, and established "species" as the basic classification of living things.

Ray

(rī), Satyajit 1921-1992.

Indian filmmaker whose works, especially the trilogy including The World of Apu (1959), offer a contemplative depiction of Bengali life.

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Satyajit Ray

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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Indo-European & Semitic Roots Appendices