light

1 of 6

noun

plural lights
1
a
: something that makes vision possible
God said, "Let there be light"; and there was light.Genesis 1:3 (Revised Standard Version)
b
: the sensation aroused by stimulation of the visual receptors
… phosphenes—the random blotches and tiny speckles of light you see when you close your eyes or in total darkness …Eric Haseltine
c
: electromagnetic radiation of any wavelength that travels in a vacuum with a speed of 299,792,458 meters (about 186,000 miles) per second
specifically : such radiation that is visible to the human eye
2
a
: daylight
… was up each morning at the first lightFrank O'Connor
b
: dawn
3
: a source of light: such as
a
: a celestial body
the lights in the sky
b
: candle
"… I crawled back to bed, and blew out the lights. …"Edith Wharton
c
: an electric light
lights can flicker when bulbs are not screwed in tightly …The Highlands News-Sun (Sebring, Florida)
4
a
: a color of notable lightness : a light or pale color
usually plural
… will lead artists through simple shapes, lights and darks, color and texture …Kathaleen Roberts
b
lights plural : clothing that is light in color
always washed the lights separately from the darks
5
archaic : sight sense 4a
6
a
: spiritual illumination
The light shines in the darkness, and the darkness has not overcome it.John 1:5 (Revised Standard Version)
c
: enlightenment
… reaching out and groping for a pathway to the light.Benjamin N. Cardozo
d
: truth
7
a
: public knowledge
facts brought to light
b
: a particular aspect or appearance presented to view
saw the matter in a different light
8
: a particular illumination
in the light of the fire
The large windows allow in lots of natural light.
9
: something that enlightens or informs
shed some light on the problem
10
: a medium (such as a window) through which light is admitted
11
lights plural : a set of principles, standards, or opinions
… worship according to one's lightsAdrienne Koch
12
: a noteworthy person in a particular place or field
a literary light among current writers
see also leading light
13
: a particular expression of the eye
listened with a fiery light burning in her eyesSherwood Anderson
14
b
: traffic light
waited for the light to change
15
: the representation of light in art
the artist's use of light and shadow
16
: a flame for lighting something (such as a cigarette)
asked a stranger for a light

light

2 of 6

adjective (1)

lighter; lightest
1
: having light : bright
a light airy room
2
a
: not intense in color, coloring, or pigmentation : not dark : pale
light hair
b
of colors : medium in saturation and high in lightness
light blue
3
of coffee : served with extra milk or cream

light

3 of 6

verb (1)

lit ˈlit How to pronounce light (audio) or lighted; lighting

intransitive verb

1
: to become light : brighten
usually used with up
Her face lit up.
2
: to catch fire
The match wouldn't light.
3
: to ignite something (such as a cigarette)
often used with up
You can't light up in here.

transitive verb

1
: to set fire to
light a candle
2
a
: to conduct with a light : guide
And all our yesterdays have lighted fools / The way to dusty death.William Shakespeare
b
: illuminate
rockets light up the sky
c
: animate, brighten
a smile lit up her face

light

4 of 6

adjective (2)

1
a
: having little weight : not heavy
a light box
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
a
: of little importance : trivial
the allegations are no light matter
b
: not abundant
light rain
a light lunch
3
a
: easily disturbed
a light sleeper
b
: exerting a minimum of force or pressure : gentle
a light touch/breeze
c
: resulting from a very slight pressure : faint
light print
4
a
: easily endurable
a light illness
b
: requiring little effort
light work
5
: capable of moving swiftly or nimbly
light on his feet
6
a
: frivolous sense 1a
light conduct
b
dated : lacking in stability : changeable
… a man of light nature and shifty methods …Susan M. Francis
c
: sexually promiscuous
7
: free from care : cheerful
in a light mood
8
: less powerful but usually more mobile than usual for its kind
light cavalry
a light cruiser
9
a
: made with a lower calorie content or with less of some ingredient (such as salt, fat, or alcohol) than usual
light beer
b
: having a relatively mild flavor
10
a
: easily digested
a light soup
b
: well leavened
a light crust
11
: coarse and sandy or easily pulverized
light soil
12
: dizzy, giddy
felt light in the head
13
: intended chiefly to entertain
light verse
light comedy
14
a
: carrying little or no cargo
the ship returned light
b
: producing goods for direct consumption by the consumer
light industry
15
: not bearing a stress or accent
a light syllable
16
: having a clear soft quality
a light voice
17
: being in debt to the pot in a poker game
three chips light
18
: short sense 5d
light on experience
19
: casual, occasional
a light drinker
lightish adjective

light

5 of 6

adverb

1
2
: with little baggage
travel light

light

6 of 6

verb (2)

lit ˈlit How to pronounce light (audio) or lighted; lighting

intransitive verb

1
2
: settle, alight
a bird lit on the lawn
3
: to fall unexpectedly
usually used with on or upon
4
: to arrive by chance : happen
usually used with on or upon
lit upon a solution
Phrases
in the light of
1
a
: from the point of view of
… he saw her in the light of compassion …Henry Fielding
… we tend to assess events not in the light of reason but with the flames of partisan passion.Jon Meacham
b
dated : in the capacity, character, condition, or role of : as entry 4
In short, he regarded me scientifically in the light of a patient …Charlotte Brontë
2
or in light of : in consideration of
In light of their findings, new procedures were established.
light into
: to attack forcefully
… she lit into the food. She didn't waste time with a fork or spoon.Donald Goines
When the boys were assembled he lit into them. Why don't you clean up this place? You're men now …James A. Michener
Choose the Right Synonym for 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

Examples of light in a Sentence

Noun The landscape was bathed in light. a photograph taken in low light the light of the moon a mixture of light and shadow The windows let fresh air and light into the room. The lights suddenly went out. The lights suddenly came on. the twinkling lights of the city below the bright lights of Broadway The lights are on, so there must be somebody at home. Adjective (1) the light, airy room is exceptionally cheerful we painted the walls a light blue her light skin tends to freckle easily in the sun Verb (1) we lit the kindling before adding the heavier logs the lights from the TV cameras will light this room as though it were high noon Adjective (2) the suitcase was as light as a feather after all the clothes were removed a little light work was all it took to straighten up the room traffic on the highway seems to be very light today the dancer was exceptionally light on her feet light punishment to fit a minor offense the waves had an especially light foam at their crests because of the strong breeze Verb (2) the bird lit on the branch and began to sing he hurriedly lighted from the bus and started walking up the street
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Noun
For light browsing and email, 20 GB to 50 GB per month is suitable. Roxanne Downer, USA Today, 29 Oct. 2025 As the Netflix series often attempted to bring light to the real mistreatment faced by incarcerated people, Poussey’s death at the hands of a police officer who suffocated her was intended to shed light on the real police brutality Black inmates in particular face. Catherine Mhloyi, Them., 29 Oct. 2025
Adjective
Her cheeks are covered with light freckles that intensify down her neck and into the collar of her uniform. Literary Hub, 5 Nov. 2025 The following episode kicks off on a much lighter note with the lawyers all sitting around trading their favorite cosmetic procedures and self-care rituals. Tom Smyth, Vulture, 5 Nov. 2025
Verb
Swinging from the overhanging branches and darting through the woods, the animals were heading toward a nearby housing project, their pink faces lit with glee. Ava Kofman, New Yorker, 3 Nov. 2025 Bailey lit the Yellow Jackets up through the air, completing 24 of 32 attempts for 340 yards and two touchdowns. Manny Navarro, New York Times, 2 Nov. 2025 See All Example Sentences for light

Word History

Etymology

Noun

Middle English liht, light, going back to Old English lēoht, Anglian lēht, going back to Germanic *leuh-t-, neuter noun (whence also Old Frisian liācht "light," Old Saxon lioht, Middle Dutch licht, lich, Old High German lioht), probably syncopated from an earlier consonantal stem *leuhađa-, as in Gothic liuhaþ "light," derivative of an Indo-European base *leu̯k- "become bright," whence also Old Irish lóchet "flash of lightning," Welsh llug "light, radiance," llug y dydd "daybreak," amlwg "clear, easily seen" (< *ambi-luk- with zero-grade), Latin lūceō, lūcēre "to emit light, shine" (Old Latin, "to cause to shine," with o-grade *lou̯k-), lūc-, lūx "light," Old Church Slavic luča "ray of light," Russian luč (genitive lučá), Bosnian-Croatian-Serbian lûč "kindling wood, torch" (< Slavic *lou̯k-), Old Prussian luckis "piece of firewood," Greek leukós "bright, shining, white," Armenian loys "light," Tocharian B lukṣäṃ "(s/he) brings light to, illuminates,"Sanskrit rócate "(it) shines, is bright," Avestan raociṇt- "brightening," Hittite lukta "it becomes light, dawns"

Note: Gothic liuhaþ has been compared directly with Hittite lukkatt- "dawn, next morning." See also lumen, lunar.

Adjective (1)

Middle English lyht, light, going back to Old English lēoht, Anglian lēht "filled with light, bright, clear," going back to Germanic *leuhta- (whence also Old Frisian liācht, licht "light, bright," Old Saxon lioht, Middle Dutch licht, lecht, Old High German lioht, liuhti), going back to Indo-European *leu̯k-to-, probably verbal adjective from the base *leu̯k- "become bright" — more at light entry 1

Verb (1)

Middle English lihten, lighten "to emit light, shine, dawn, shed light on, light (a fire, a candle), set fire to, illuminate," going back to Old English līohtan, līehtan, Anglian līhtan "to give light, become light, light (a candle)," going back to Germanic *leuhtije- (whence also Old Saxon liuhtan "to shine," Middle Dutch luchten, Old High German liuhten, Gothic liuhtjan "to give light"), weak verb derivative from *leuhta- "bright, light entry 2"

Adjective (2)

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

Verb (2)

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

First Known Use

Noun

before the 12th century, in the meaning defined at sense 1a

Adjective (1)

before the 12th century, in the meaning defined at sense 1

Verb (1)

before the 12th century, in the meaning defined at intransitive sense 1

Adjective (2)

before the 12th century, in the meaning defined at sense 1a

Adverb

before the 12th century, in the meaning defined at sense 1

Verb (2)

before the 12th century, in the meaning defined at sense 1

Time Traveler
The first known use of light was before the 12th century

Browse Nearby Words

Cite this Entry

“Light.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light. Accessed 5 Nov. 2025.

Kids Definition

light

1 of 6 noun
1
a
: something that makes vision possible
b
: the sensation aroused by stimulation of the visual sense organs
c
: electromagnetic radiation of any wavelength (as infrared, visible, ultraviolet, and X-rays) and traveling in a vacuum with a speed of about 186,000 miles (300,000 kilometers) per second
especially : such radiation that is visible to the human eye
2
: daylight sense 1
by dawn's early light
3
: a source (as a lamp) of light
turn on the light
4
a
: public knowledge
facts brought to light
b
: a particular appearance presented to view
were shown in a bad light by the lawyer
I see the matter in a different light now
5
: a particular illumination
by the light of the moon
6
: something that helps one to know or understand
shed light on a problem
7
: a noted person : leading light
8
b
: traffic signal
turn left at the next light
9
: a flame for lighting something

light

2 of 6 adjective
1
: having light : bright
a light room
2
: not dark or deep in color : pale
light blue
lightness noun

light

3 of 6 verb
lighted or lit ˈlit How to pronounce light (audio) ; lighting
1
: to make or become bright
often used with up
2
: to cause to burn or begin to burn
often used with up
3
: to lead with a light
light a guest up the stairs

light

4 of 6 adjective
1
a
: having little or less than usual weight : not heavy
b
: designed to carry a small load
light truck
2
a
: of little importance
b
: not abundant : scanty
light rain
c
: not strong or violent : moderate
light breezes
3
a
: easily disturbed
a light sleeper
b
: putting forth little force or pressure : gentle
a light touch
4
: not hard to bear, do, pay, or digest
light punishment
light exercise
light food
5
: capable of moving swiftly or nimbly
light on one's feet
6
: intended chiefly to entertain
light reading
light verse
7
: made with a lower calorie content or with less of some ingredient (as fat)
light salad dressing
8
: having a spongy or fluffy quality
light pastry
9
: producing goods that will be sold to the people who use them rather than to another manufacturer
light industry
lightly adverb
lightness noun

light

5 of 6 adverb
1
: in a light manner
2
: with little baggage
traveling light

light

6 of 6 verb
lighted or lit ˈlit How to pronounce light (audio) ; lighting
1
: to come down out of the air and settle : alight
birds lit on the lawn
2
: to come by chance
lit upon a solution
Etymology

Noun

Old English lēoht "light, that which makes seeing possible"

Adjective

Old English lēoht "not heavy"

Verb

Old English līhtan "to come down off something or out of the air"

Medical Definition

light

1 of 2 noun
1
a
: the sensation aroused by stimulation of the visual receptors
b
: an electromagnetic radiation in the wavelength range including infrared, visible, ultraviolet, and X-rays and traveling in a vacuum with a speed of about 186,281 miles (300,000 kilometers) per second
specifically : the part of this range that is visible to the human eye
2
: a source of light

light

2 of 2 adjective
variants or lite
: made with a lower calorie content or with less of some ingredient (as salt, fat, or alcohol) than usual
light salad dressing

More from Merriam-Webster on light

Last Updated: - Definition revised
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