something that makes things visible or affords illumination

All colors depend on light.

Physics .

Also called luminous energy , radiant energy. electromagnetic radiation to which the organs of sight react, ranging in wavelength from about 400 to 700 nm and propagated at a speed of 186,282 mi./sec (299,972 km/sec), considered variously as a wave, corpuscular, or quantum phenomenon.

a similar form of radiant energy that does not affect the retina, as ultraviolet or infrared rays.

the sensation produced by stimulation of the organs of sight.

an illuminating agent or source, as the sun, a lamp, or a beacon.

the radiance or illumination from a particular source

the light of a candle.

the illumination from the sun; daylight

We awoke at the first light.

daybreak or dawn

when light appeared in the east.

daytime

Summer has more hours of light.

a particular light or illumination in which an object seen takes on a certain appearance

viewing the portrait in dim light.

a device for or means of igniting, as a spark, flame, or match

Could you give me a light?

a traffic light

Don't cross till the light changes.

the aspect in which a thing appears or is regarded

Try to look at the situation in a more cheerful light.

the state of being visible, exposed to view, or revealed to public notice or knowledge; limelight

Stardom has placed her in the light.

a person who is an outstanding leader, celebrity, or example; luminary

He became one of the leading lights of Restoration drama.

Art .

the effect of light falling on an object or scene as represented in a picture.

one of the brightest parts of a picture.

a gleam or sparkle, as in the eyes.

a measure or supply of light; illumination

The wall cuts off our light.

spiritual illumination or awareness; enlightenment.

Architecture .

Also called day. one compartment of a window or window sash.

a window, esp. a small one.

mental insight; understanding.

lights, the information, ideas, or mental capacities possessed

to act according to one's lights.

a lighthouse.

Archaic . the eyesight.

having light or illumination; bright; well-lighted

the lightest room in the entire house.

pale, whitish, or not deep or dark in color

a light blue.

(of coffee or tea) containing enough milk or cream to produce a light color.

to set burning, as a candle, lamp, fire, match, or cigarette; kindle; ignite.

to turn or switch on (an electric light)

One flick of the master switch lights all the lamps in the room.

to give light to; furnish with light or illumination

The room is lighted by two large chandeliers.

to make (an area or object) bright with or as if with light (often fol. by up )

Hundreds of candles lighted up the ballroom.

to cause (the face, surroundings, etc.) to brighten, esp. with joy, animation, or the like (often fol. by up )

A smile lit up her face. Her presence lighted up the room.

to guide or conduct with a light

a candle to light you to bed.

to take fire or become kindled

The damp wood refused to light.

to ignite a cigar, cigarette, or pipe for purposes of smoking (usually fol. by up )

He took out a pipe and lighted up before speaking.

to become illuminated when switched on

This table lamp won't light.

to become bright, as with light or color (often fol. by up )

The sky lights up at sunset.

to brighten with animation or joy, as the face or eyes (often fol. by up ). ?

bring to light

to discover or reveal

The excavations brought to light the remnants of an ancient civilization.

come to light

to be discovered or revealed

Some previously undiscovered letters have lately come to light.

hide one's light under a bushel

to conceal or suppress one's talents or successes.

in a good (or bad ) light

under favorable (or unfavorable) circumstances

She worshiped him, but then she'd only seen him in a good light.

in (the) light of

taking into account; because of; considering

It was necessary to review the decision in the light of recent developments.

light at the end of the tunnel, a prospect of success, relief

or redemption

We haven't solved the problem yet, but we're beginning to see light at the end of the tunnel.

see the light

to come into existence or being.

to be made public.

to begin to accept or understand a point of view one formerly opposed

Her father was opposed to her attending an out-of-town college, but he finally saw the light.

shed or throw light on

to clarify; clear up

His deathbed confession threw light on a mystery of long standing.

adjective

black , dark , darkened , dim , gloomy , obscure , brunette , dusky , heavy , weighted , difficult , laborious , grave , serious , solemn

noun

dark , darkness , night , obscurity , misconception , misunderstanding

verb

darken , dull , obscure , drench , extinguish , put out , quench , mount

adjective

ablaze , aglow , bright , brilliant , burnished , clear , cloudless , flashing , fluorescent , glossy , glowing , lambent , lucent , luminous , lustrous , phosphorescent , polished , radiant , refulgent , resplendent , rich , scintillant , shining , shiny , sunny , unclouded , unobscured , vivid , well-lighted , well-lit , bleached , faded , fair-skinned , light-hued , light-skinned , light-toned , pale , pastel , tow-headed , agile , airy , atmospheric , buoyant , crumbly , dainty , delicate , downy , easy , effervescent , ethereal , featherweight , feathery , filmy , flimsy , floatable , floating , fluffy , friable , frothy , gossamery , graceful , imponderous , inconsequential , insubstantial , light-footed , lightweight , lithe , little , loose , meager , nimble , petty , porous , portable , sandy , sheer , slender , slight , small , spongy , sprightly , sylphlike , thin , tissuelike , trifling , trivial , unheavy , unsubstantial , weightless , casual , digestible , faint , fractional , fragmentary , frivolous , frugal , gentle , hardly any , hardly enough , inadequate , inconsiderable , indistinct , insignificant , insufficient , mild , minor , minuscule , minute , moderate , modest , not many , not much , not rich , puny , restricted , scanty , shoestring * , soft , sparse , superficial , tiny , unimportant , weak , wee , effortless , facile , manageable , smooth , undemanding , unexacting , untaxing , untroublesome , amusing , animated , blithe , carefree , cheerful , chipper * , chirpy , diverting , dizzy , entertaining , fickle , flighty , gay , giddy , high , humorous , lighthearted , lively , merry , perky , pleasing , sunny-side up , up , upbeat , witty , alabaster , ivory

noun

aurora , beacon , blaze , brightness , brilliance , brilliancy , bulb , candle , coruscation , dawn , daybreak , daylight , daytime , effulgence , emanation , flare , flash , fulgor , glare , gleam , glimmer , glint , glitter , glow , illumination , incandescence , irradiation , lambency , lamp , lantern , lighthouse , luminosity , luster , morn , morning , phosphorescence , radiance , radiation , ray , refulgence , scintillation , sheen , shine , sparkle , splendor , star , sun , sunbeam , sunrise , sunshine , taper , torch , window , angle , approach , aspect , attitude , awareness , comprehension , condition , education , elucidation , enlightenment , example , exemplar , explanation , illustration , information , insight , interpretation , knowledge , model , paragon , slant , standing , vantage point , viewpoint , lighting , facet , frame of reference , hand , regard , respect , side , eye , eyesight , seeing , sight

verb

animate , brighten , cast , fire , flood , floodlight , furnish with light , highlight , ignite , illume , illumine , inflame , irradiate , kindle , lighten , light up , limelight , make bright , make visible , put on , shine , spot , spotlight , switch on , turn on , burn , enkindle , flame , set fire to , set on fire , spark , strike a match , alight , arrive , come down , deplane , detrain , disembark , drop , fly down , get down , perch , rest , roost , set down , settle , settle down , sit , sit down , stop , touch down , enliven