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ray 1 (rā)
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n.
1.
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.]

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
ray 2 (rā)
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n.
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

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Ray (rā), John 1627-1705.
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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.

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 
Ray (rī), Satyajit 1921-1992.
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Indian filmmaker whose works, especially the trilogy including The World of Apu (1959), offer a contemplative depiction of Bengali life.
(click for a larger image)
Satyajit Ray

The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2017 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
 

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