ray

/reɪ/

/reɪ/

Other forms: rays; rayed; raying

A ray is a beam of light or radiation. Even on cloudy days, you sometimes see a ray of sunlight shine through the clouds.

In physics, a ray is a line or column of light, heat, or electromagnetic radiation (like an x-ray), while in math a ray is a line that passes through a specific point. A marine biologist would define a ray as a big fish that's related to sharks and has a wide, flat body and a long tail. The root of the first two kinds of rays is the Latin word radius, "spoke" or "staff."

Definitions of ray

1. noun

   a group of nearly parallel lines of electromagnetic radiation
   synonyms: beam, electron beam

   types:

   cathode ray

   a beam of electrons emitted by the cathode of an electrical discharge tube

   particle beam

   a collimated flow of particles (atoms or electrons or molecules)

   ion beam, ionic beam

   a beam of ions moving in the same direction at the same speed

   type of:

   electromagnetic radiation, electromagnetic wave, nonparticulate radiation

   radiation consisting of waves of energy associated with electric and magnetic fields resulting from the acceleration of an electric charge
2. noun

   a column of light (as from a beacon)
   synonyms: beam, beam of light, irradiation, light beam, ray of light, shaft, shaft of light

   types:

   heat ray

   a ray that produces a thermal effect

   high beam

   the beam of a car's headlights that provides distant illumination

   moon ray, moon-ray, moonbeam

   a ray of moonlight

   sunbeam, sunray

   a ray of sunlight

   laser beam

   a beam of light generated by a laser

   low beam

   the beam of a car's headlights that provides illumination for a short distance

   infrared ray

   a ray of infrared radiation; produces a thermal effect (as from an infrared lamp)

   type of:

   light, visible light, visible radiation

   (physics) electromagnetic radiation that can produce a visual sensation
3. noun

   (mathematics) a straight line extending from a point
   type of:

   vector

   a straight line segment whose length is magnitude and whose orientation in space is direction
4. verb

   emit as rays
   “That tower rays a laser beam for miles across the sky”

   type of:

   emit, give off, give out

   give off, send forth, or discharge; as of light, heat, or radiation, vapor, etc.
5. verb

   extend or spread outward from a center or focus or inward towards a center
   synonyms: radiate

   type of:

   extend, go, lead, pass, run

   stretch out over a distance, space, time, or scope; run or extend between two points or beyond a certain point
6. verb

   expose to radiation
   synonyms: irradiate

   types:

   bombard

   direct high energy particles or radiation against

   type of:

   process, treat

   subject to a process or treatment, with the aim of readying for some purpose, improving, or remedying a condition
7. noun

   a branch of an umbel or an umbelliform inflorescence
   type of:

   pedicel, pedicle

   a small stalk bearing a single flower of an inflorescence; an ultimate division of a common peduncle
8. noun

   the syllable naming the second (supertonic) note of any major scale in solmization
   synonyms: re

   type of:

   solfa syllable

   one of the names for notes of a musical scale in solmization
9. noun

   any of the stiff bony spines in the fin of a fish
   type of:

   spine

   a sharp rigid animal process or appendage; as a porcupine quill or a ridge on a bone or a ray of a fish fin
10. noun

    cartilaginous fishes having horizontally flattened bodies and enlarged winglike pectoral fins with gills on the underside; most swim by moving the pectoral fins
    types:

    crampfish, electric ray, numbfish, torpedo

    any sluggish bottom-dwelling ray of the order Torpediniformes having a rounded body and electric organs on each side of the head capable of emitting strong electric discharges

    sawfish

    primitive ray with sharp teeth on each edge of a long flattened snout

    guitarfish

    primitive tropical bottom-dwelling ray with a guitar-shaped body

    stingray

    large venomous ray with large barbed spines near the base of a thin whiplike tail capable of inflicting severe wounds

    eagle ray

    powerful free-swimming tropical ray noted for `soaring' by flapping winglike fins; usually harmless but has venomous tissue near base of the tail as in stingrays

    devilfish, manta, manta ray

    extremely large pelagic tropical ray that feeds on plankton and small fishes; usually harmless but its size make it dangerous if harpooned

    skate

    large edible rays having a long snout and thick tail with pectoral fins continuous with the head; swim by undulating the edges of the pectoral fins

    Pristis pectinatus, smalltooth sawfish

    commonly found in tropical bays and estuaries; not aggressive

    Dasyatis centroura, roughtail stingray

    one of the largest stingrays; found from Cape Cod to Cape Hatteras

    butterfly ray

    a stingray with a short tail and a broad fin

    Aetobatus narinari, spotted eagle ray, spotted ray

    ray with back covered with white or yellow spots; widely distributed in warm seas

    Rhinoptera bonasus, cow-nosed ray, cownose ray

    large ray found along eastern coast of North America

    Atlantic manta, Manta birostris

    largest manta (to 22 feet across wings); found worldwide but common in Gulf of Mexico and along southern coasts of United States; primarily oceanic

    Mobula hypostoma, devil ray

    small manta (to 4 feet) that travels in schools

    Raja batis, gray skate, grey skate

    common European skate used as food

    Raja erinacea, little skate

    most plentiful skate in North American inshore waters in summer; to 21 inches

    Raja radiata, thorny skate

    cold-water bottom fish with spines on the back; to 40 inches

    Raja laevis, barndoor skate

    one of the largest skates (to 5 feet); an active skate easy to hook

    type of:

    elasmobranch, selachian

    any of numerous fishes of the class Chondrichthyes characterized by a cartilaginous skeleton and placoid scales: sharks; rays; skates