ray

ray¹

—raylike, adj.

/ray/, n.

1. a narrow beam of light.

2. a gleam or slight manifestation: a ray of hope.

3. a raylike line or stretch of something.

4. light or radiance.

5. a line of sight.

6. Physics, Optics.

a. any of the lines or streams in which light appears to radiate from a luminous body.

b. the straight line normal to the wave front in the propagation of radiant energy.

c. a stream of material particles all moving in the same straight line.

7. Math.

a. one of a system of straight lines emanating from a point.

b. Also called half-line. the part of a straight line considered as originating at a point on the line and as extending in one direction from that point.

8. any of a system of parts radially arranged.

9. Zool.

a. one of the branches or arms of a starfish or other radiate animal.

b. one of the bony or cartilaginous rods in the fin of a fish.

10. Bot.

a. See ray flower.

b. one of the branches of an umbel.

c. See vascular ray.

d. (in certain composite plants) the marginal part of the flower head.

11. Astron. one of many long, bright streaks radiating from some of the large lunar craters.

12. a prominent upright projection from the circlet of a crown or coronet, having a pointed or ornamented termination.

13. get or grab some rays, Slang. to relax in the sun, esp. to sunbathe.

v.i.

14. to emit rays.

15. to issue in rays.

v.t.

16. to send forth in rays.

17. to throw rays upon; irradiate.

18. to subject to the action of rays, as in radiotherapy.

19. Informal. to make a radiograph of; x-ray.

20. to furnish with rays or radiating lines.

[1300-50; ME raie, raye < OF rai < L radius RADIUS]

Syn. 1. See gleam.

ray²

/ray/, n.

any of numerous elasmobranch fishes, adapted for life on the sea bottom, having a flattened body and greatly enlarged pectoral fins with the gills on the undersides.

[1275-1325; ME raye ( < OF rai) < L raia]

* * *

I

Any of 300–350 mostly marine species of cartilaginous fish (order Batoidei) found worldwide and classified as electric rays, sawfishes, skates, and stingrays.

Many species are slow-moving bottom-dwellers. The gill openings and mouth are on the underside of the flattened body. Winglike pectoral fins extend along the sides of the head. All but electric rays have a long, slender tail, often with saw-edged, venomous spines, and rough, often spiny, skin. See also manta ray.

II

(as used in expressions)

cathode ray oscilloscope

whip tailed ray

Bob and Ray

Bradbury Ray Douglas

cathode ray

cathode ray tube

Charles Ray

Ray Charles Robinson

cosmic ray

Delany Samuel Ray

Eames Charles and Ray

electric ray

gamma ray

gamma ray astronomy

Leonard Sugar Ray

Ray Charles Leonard

Man Ray

manta ray

devil ray

Milland Ray

Ray James Earl

Ray John

Ray Nicholas

Ray Satyajit

Robinson Sugar Ray

Alvin Ray Rozelle

X ray

X ray astronomy

X ray diffraction

* * *

▪ fish

      any of the cartilaginous fishes of the order Batoidei, related to sharks (shark) and placed with them in the class Chondrichthyes. The order includes 534 species.

      Rays are distinguished from sharks by a flattened, disklike body, with the five gill openings and the mouth generally located on the underside. Rays are further distinguished from sharks by their greatly enlarged, winglike pectoral fins, which extend forward along the sides of the head above the gill openings. Many rays swim and breathe differently from sharks, propelling themselves with their pectoral fins and taking in water for respiration through large openings (spiracles) on the upper surface of the head, rather than through the mouth. The ray's tail is generally long and slender and in many species bears one or more sharp, saw-edged, venomous spines that can be used to inflict painful wounds.

      Rays are predominantly marine and are found in all oceans. Many are slow-moving bottom dwellers. Manta rays (manta ray) feed on plankton and small animals; others take various fishes and invertebrates, sometimes damaging commercially valuable shellfish beds. Other than skates, most or possibly all rays bear living young. Fertilization is internal, the male introducing sperm into the female by means of special copulatory organs (claspers) that are the modified edges of the pelvic fins.

      Rays can be classified into the following groups: electric rays, sawfishes, skates, and various families of rays that have slender, whiplike tails equipped with spines and that are all-inclusively called stingrays (stingray), or whip-tailed rays.

      The electric rays (electric ray) (suborder Torpedinoidei) are distinguished by large paired electric organs between the pectoral fins and the head, with which they can give powerful shocks either for defensive purposes or to kill prey. The electric rays have a smooth and naked skin; the head and trunk with the pectoral fins form a circular disk, and the tail is short and stout. About 20 species are known to inhabit warm seas, with some reaching a weight of 200 pounds (90 kg).

      All other types of rays, which lack electric organs, generally have a rough skin, often bearing strong spines. The sawfishes (sawfish) (family Pristidae) have a snout that is modified into a long blade possessing a series of strong teeth on each side. About six species are known from warm seas, frequenting sandy shores and estuaries.

      In the skates (skate) (suborder Rajoidei), the large pectoral fins extend to the snout and backward, stopping abruptly at the base of a slender tail. In contrast to other rays, skates produce eggs; these are large and oblong in shape with dark, leathery shells having a tendril at each corner by which they become fastened to seaweed or other objects. Skates lack the long, slender barbed spine that distinguishes stingrays. The most widespread skates belong to the genus Raja of the family Rajidae.

      The remaining rays comprise the suborder Myliobatoidei (eagle ray) and consist of whip-tailed rays (family Dasyatidae), butterfly rays (Gymnuridae), stingrays (Urolophidae), eagle rays (Myliobatidae), manta rays (or devil rays; Mobulidae), and cow-nosed rays (Rhinopteridae). Common to the rays of all these families is a long, slender, whiplike tail that usually has a barbed spine connected with a poison gland; this spine is capable of inflicting serious wounds and is a dangerous weapon when the tail is lashed. Almost all of these rays are inhabitants of warm seas, except for a few species of stingray that live in the rivers of South America.

      The guitarfishes (guitarfish) are a group of fishes that are closely related to the rays and are either classified as a separate order (Rhinobatiformes) or as a suborder (Rhinobatoidei) of the ray order (Batoidei).

      For more information on species and groups of rays, see manta ray; electric ray; guitarfish; sawfish; skate; stingray. (stingray)

* * *