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noun \ˈlīt\

Simple Definition of light

  • : the form of energy that makes it possible to see things : the brightness produced by the sun, by fire, a lamp, etc.

  • : a source of light (such as an electric lamp)

  • : a light on a vehicle

Full Definition of light

  1. 1 a :  something that makes vision possible b :  the sensation aroused by stimulation of the visual receptors c :  electromagnetic radiation of any wavelength that travels in a vacuum with a speed of about 186,281 miles (300,000 kilometers) per second; specifically :  such radiation that is visible to the human eye

  2. 2 a :  daylight b :  dawn

  3. 3 :  a source of light: as a :  a celestial body b :  candle c :  an electric light

  4. 4 archaic :  sight 4a

  5. 5 a :  spiritual illumination b :  inner light c :  enlightenment d :  truth

  6. 6 a :  public knowledge <facts brought to light> b :  a particular aspect or appearance presented to view <saw the matter in a different light>

  7. 7 :  a particular illumination

  8. 8 :  something that enlightens or informs <shed some light on the problem>

  9. 9 :  a medium (as a window) through which light is admitted

  10. 10 plural :  a set of principles, standards, or opinions <worship according to one's lights — Adrienne Koch>

  11. 11 :  a noteworthy person in a particular place or field <a leading light among current writers>

  12. 12 :  a particular expression of the eye

  13. 13 a :  lighthouse, beacon b :  traffic light

  14. 14 :  the representation of light in art

  15. 15 :  a flame for lighting something (as a cigarette)

in the light of
  1. 1 :  from the point of view of

  2. 2 or in light of :  in view of <in light of their findings, new procedures were established>

Examples of light

  1. The landscape was bathed in light.

  2. a photograph taken in low light

  3. the light of the moon

  4. a mixture of light and shadow

  5. The windows let fresh air and light into the room.

  6. The lights suddenly went out.

  7. The lights suddenly came on.

  8. the twinkling lights of the city below

  9. the bright lights of Broadway

  10. The lights are on, so there must be somebody at home.

Origin of light

Middle English, from Old English lēoht; akin to Old High German lioht light, Latin luc-, lux light, lucēre to shine, Greek leukos white

First Known Use: before 12th century




Definition of light

  1. 1 :  having light :  bright <a light airy room>

  2. 2 a :  not dark, intense, or swarthy in color or coloring :  pale b of colors :  medium in saturation and high in lightness <light blue>

  3. 3 of coffee :  served with extra milk or cream

Before 12th Century

First Known Use of light

before 12th century




Definition of light

lit play \ˈlit\ or light·edlight·ing

  1. intransitive verb
  2. 1 :  to become light :  brighten —usually used with up <her face lit up>

  3. 2 :  to take fire

  4. 3 :  to ignite something (as a cigarette) —often used with up

  5. transitive verb
  6. 1 :  to set fire to

  7. 2 a :  to conduct with a light :  guide b :  illuminate <rockets light up the sky> c :  animate, brighten <a smile lit up her face>

Before 12th Century

First Known Use of light

before 12th century




Definition of light

  1. 1 a :  having little weight :  not heavy b :  designed to carry a comparatively small load <a light truck> c :  having relatively little weight in proportion to bulk <aluminum is a light metal> d :  containing less than the legal, standard, or usual weight <a light coin>

  2. 2 a :  of little importance :  trivial b :  not abundant <light rain> <a light lunch>

  3. 3 a :  easily disturbed <a light sleeper> b :  exerting a minimum of force or pressure :  gentle <a light touch> c :  resulting from a very slight pressure :  faint <light print>

  4. 4 a :  easily endurable <a light illness> b :  requiring little effort <light work>

  5. 5 :  capable of moving swiftly or nimbly <light on his feet>

  6. 6 a :  frivolous 1a <light conduct> b :  lacking in stability :  changeable <light opinions> c :  sexually promiscuous

  7. 7 :  free from care :  cheerful

  8. 8 :  less powerful but usually more mobile than usual for its kind <light cavalry> <a light cruiser>

  9. 9 a :  made with a lower calorie content or with less of some ingredient (as salt, fat, or alcohol) than usual b :  having a relatively mild flavor

  10. 10 a :  easily digested <a light soup> b :  well leavened <a light crust>

  11. 11 :  coarse and sandy or easily pulverized <light soil>

  12. 12 :  dizzy, giddy <felt light in the head>

  13. 13 :  intended chiefly to entertain <light verse> <light comedy>

  14. 14 a :  carrying little or no cargo <the ship returned light> b :  producing goods for direct consumption by the consumer <light industry>

  15. 15 :  not bearing a stress or accent <a light syllable>

  16. 16 :  having a clear soft quality <a light voice>

  17. 17 :  being in debt to the pot in a poker game <three chips light>

  18. 18 :  short 5d <light on experience>

  19. 19 :  casual, occasional <a light smoker>

light·ish play \ˈlī-tish\ adjective

Origin of light

Middle English, from Old English lēoht; akin to Old High German līhti light, Latin levis, Greek elachys small

First Known Use: before 12th century

Synonym Discussion of light

easy, facile, simple, light, effortless, smooth mean not demanding effort or involving difficulty. easy is applicable either to persons or things imposing tasks or to activity required by such tasks <an easy college course>. facile often adds to easy the connotation of undue haste or shallowness <facile answers to complex questions>. simple stresses ease in understanding or dealing with because complication is absent <a simple problem in arithmetic>. light stresses freedom from what is burdensome <a light teaching load>. effortless stresses the appearance of ease and usually implies the prior attainment of artistry or expertness <moving with effortless grace>. smooth stresses the absence or removal of all difficulties, hardships, or obstacles <a smooth ride>.




Definition of light

  1. 1 :  lightly

  2. 2 :  with little baggage <travel light>

Before 12th Century

First Known Use of light

before 12th century




Definition of light

lit play \ˈlit\ or light·edlight·ing

  1. intransitive verb
  2. 1 :  dismount

  3. 2 :  settle, alight <a bird lit on the lawn>

  4. 3 :  to fall unexpectedly —usually used with on or upon

  5. 4 :  to arrive by chance :  happen —usually used with on or upon <lit upon a solution>

light into
  1. :  to attack forcefully <I lit into that food until I'd finished off the heel of the loaf — Helen Eustis>

Origin of light

Middle English, from Old English līhtan; akin to Old English lēoht light in weight

First Known Use: before 12th century

Seen and Heard

What made you want to look up light? Please tell us where you read or heard it (including the quote, if possible).


February 8, 2016

to clear from accusation or blame

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