light

It's pitch black in your room so you switch on the lamp, and your room is filled with light. Light is a source of illumination, whether a natural one (like the sun) or an artificial one (like your lamp).

Like light itself, the word can take a lot of different forms — it can be a noun, an adjective, or a verb, and it can mean "bright" or "not heavy". No matter how you define it, though, the word comes from the Old English word leoht.

Primary Meanings of light

1.
nadjv
(physics) electromagnetic radiation that can produce a visual sensation
characterized by or emitting light
make lighter or brighter
2.
adjadv
of comparatively little physical weight or density
with few burdens
3.
vn
cause to start burning; subject to fire or great heat
a device for lighting or igniting fuel or charges or fires
4.
v
to come to rest, settle
5.
adj
(used of soil) loose and large-grained in consistency
Full Definitions of light
1

n (physics) electromagnetic radiation that can produce a visual sensation

“the light was filtered through a soft glass window”
Synonyms:
visible light, visible radiation
Types:
show 37 types...
hide 37 types...
beam, beam of light, irradiation, light beam, ray, ray of light, shaft, shaft of light
a column of light (as from a beacon)
candle flame, candlelight
the light provided by a burning candle
corona
one or more circles of light seen around a luminous object
counterglow, gegenschein
a faint spot of light in the night sky that appears directly opposite the position of the sun; a reflection of sunlight by micrometeoric material in space
daylight
light during the daytime
firelight
the light of a fire (especially in a fireplace)
fluorescence
light emitted during absorption of radiation of some other (invisible) wavelength
friar's lantern, ignis fatuus, jack-o'-lantern, will-o'-the-wisp
a pale light sometimes seen at night over marshy ground
gaslight
light yielded by the combustion of illuminating gas
glow, glowing, radiance
the amount of electromagnetic radiation leaving or arriving at a point on a surface
glow
a steady even light without flames
half-light
a greyish light (as at dawn or dusk or in dim interiors)
glow, incandescence
the phenomenon of light emission by a body as its temperature is raised
lamplight
light from a lamp
luminescence
light not due to incandescence; occurs at low temperatures
meteor, shooting star
a streak of light in the sky at night that results when a meteoroid hits the earth's atmosphere and air friction causes the meteoroid to melt or vaporize or explode
Moon, moonlight, moonshine
the light of the Moon
starlight
the light of the stars
sun, sunlight, sunshine
the rays of the sun
scintillation
(physics) a flash of light that is produced in a phosphor when it absorbs a photon or ionizing particle
streamer
light that streams
torchlight
light from a torch or torches
twilight
the diffused light from the sky when the sun is below the horizon but its rays are refracted by the atmosphere of the earth
aureole, corona
the outermost region of the sun's atmosphere; visible as a white halo during a solar eclipse
autofluorescence
self-induced fluorescence
sky glow
illumination of the night sky in urban areas
heat ray
a ray that produces a thermal effect
high beam
the beam of a car's headlights that provides distant illumination
bioluminescence
luminescence produced by physiological processes (as in the firefly)
chemiluminescence
luminescence resulting from a chemical reaction as the oxidation of luciferin in fireflies
bolide, fireball
an especially luminous meteor (sometimes exploding)
moon ray, moon-ray, moonbeam
a ray of moonlight
sunburst
a sudden emergence of the sun from behind clouds
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
phosphorescence
a fluorescence that persists after the bombarding radiation has ceased
Type of:
actinic radiation, actinic ray
electromagnetic radiation that can produce photochemical reactions

n the quality of being luminous; emitting or reflecting light

Synonyms:
brightness, brightness level, luminance, luminosity, luminousness
Types:
illuminance, illumination
the luminous flux incident on a unit area
incandescence
light from heat
glow, luminescence
light from nonthermal sources
Type of:
physical property
any property used to characterize matter and energy and their interactions

n an illuminated area

“he stepped into the light
Type of:
scene
the place where some action occurs

n the visual effect of illumination on objects or scenes as created in pictures

“he could paint the lightest light and the darkest dark”
Synonyms:
lightness
Types:
show 13 types...
hide 13 types...
aura, aureole, gloriole, glory, halo, nimbus
an indication of radiant light drawn around the head of a saint
sunniness
lightness created by sunlight
highlight, highlighting
an area of lightness in a picture
brightness
the location of a visual perception along a continuum from black to white
cloudlessness
the lightness of a sunny day when there are no clouds in the sky
blaze, brilliance, glare
a light within the field of vision that is brighter than the brightness to which the eyes are adapted
dazzle
brightness enough to blind partially and temporarily
glisten, glister, glitter, scintillation, sparkle
the quality of shining with a bright reflected light
flash
a momentary brightness
glint
a spatially localized brightness
iridescence, opalescence
the visual property of something having a milky brightness and a play of colors from the surface
effulgence, radiance, radiancy, refulgence, refulgency, shine
the quality of being bright and sending out rays of light
brilliancy, luster, lustre, splendor, splendour
a quality that outshines the usual
Type of:
visual property
an attribute of vision

n having abundant light or illumination

“they played as long as it was light
Synonyms:
lighting
Antonyms:
dark, darkness
absence of light or illumination
Type of:
illumination
the degree of visibility of your environment

n any device serving as a source of illumination

“he stopped the car and turned off the lights
Synonyms:
light source
Types:
show 20 types...
hide 20 types...
anchor light, riding lamp, riding light
a light in the rigging of a ship that is riding at anchor
blinker, flasher
a light that flashes on and off; used as a signal or to send messages
fairy light
a small colored light used for decoration (especially at Christmas)
flood, flood lamp, floodlight, photoflood
light that is a source of artificial illumination having a broad beam; used in photography
headlamp, headlight
a powerful light with reflector; attached to the front of an automobile or locomotive
houselights
lights that illuminate the audience's part of a theater or other auditorium
jacklight
a light used as a lure in hunting or fishing at night
navigation light
light on an airplane that indicates the plane's position and orientation; red light on the left (port) wing tip and green light on the right (starboard) wing tip
night-light
light (as a candle or small bulb) that burns in a bedroom at night (as for children or invalids)
panel light
a light to illuminate an instrument panel
room light
light that provides general illumination for a room
sconce
a candle or flaming torch secured in a sconce
searchlight
a light source with reflectors that projects a beam of light in a particular direction
running light, sidelight
light carried by a boat that indicates the boat's direction; vessels at night carry a red light on the port bow and a green light on the starboard bow
strip lighting
light consisting of long tubes (instead of bulbs) that provide the illumination
theater light
any of various lights used in a theater
torch
a light usually carried in the hand; consists of some flammable substance
flambeau
a flaming torch (such as are used in processions at night)
foglamp
headlight that provides strong beam for use in foggy weather
footlights
theater light at the front of a stage that illuminate the set and actors
Type of:
source of illumination
any device serving as a source of visible electromagnetic radiation

n a visual warning signal

“they saw the light of the beacon”
“there was a light at every corner”
Types:
show 4 types...
hide 4 types...
stoplight, traffic light, traffic signal
a visual signal to control the flow of traffic at intersections
go-ahead, green light
a signal to proceed
red light
the signal to stop
yellow light
the signal to proceed with caution
Type of:
visual signal
a signal that involves visual communication

n a particular perspective or aspect of a situation

“although he saw it in a different light, he still did not understand”
Type of:
perspective, position, view
a way of regarding situations or topics etc.

n public awareness

“it brought the scandal to light
Type of:
general knowledge, public knowledge
knowledge that is available to anyone

n mental understanding as an enlightening experience

“he finally saw the light
“can you shed light on this problem?”
Type of:
brainstorm, brainwave, insight
the clear (and often sudden) understanding of a complex situation

n a condition of spiritual awareness; divine illumination

“follow God's light
Synonyms:
illumination
Type of:
condition, status
a state at a particular time

n a person regarded very fondly

“the light of my life”
Type of:
friend
a person you know well and regard with affection and trust

n merriment expressed by a brightness or gleam or animation of countenance

Synonyms:
spark, sparkle, twinkle
Type of:
verve, vitality
an energetic style
aspect, expression, face, facial expression, look
the feelings expressed on a person's face

adj characterized by or emitting light

“a room that is light when the shutters are open”
“the inside of the house was airy and light
Synonyms:
ablaze, inflamed, reddened
lighted with red light as if with flames
autofluorescent
emitting light via self-induced fluorescence
bioluminescent
(of living organisms) emitting light
bright
having lots of light either natural or artificial
candescent
glowing from great heat
floodlighted, floodlit
illuminated by means of floodlights
fluorescent
emitting light during exposure to radiation from an external source
illuminated, lighted, lit, well-lighted
provided with artificial light
candent, incandescent
emitting light as a result of being heated
lamplit
lighted by a lamp
lighting-up
turning lights on
livid
(of a light) imparting a deathlike luminosity
luminescent
emitting light not caused by heat
phosphorescent
emitting light without appreciable heat as by slow oxidation of phosphorous
sunlit, sunstruck
lighted by sunlight
white
of summer nights in northern latitudes where the sun barely sets
Antonyms:
dark
devoid of or deficient in light or brightness; shadowed or black
Acheronian, Acherontic, Stygian
dark and dismal as of the rivers Acheron and Styx in Hades
aphotic
lacking light; especially not reached by sunlight
black, pitch-black, pitch-dark
extremely dark
caliginous
dark and misty and gloomy
Cimmerian
intensely dark and gloomy as with perpetual darkness
crepuscular
like twilight; dim
darkened
become or made dark by lack of light
darkening
becoming dark or darker as from waning light or clouding over
darkling
(poetic) occurring in the dark or night
darkling
uncannily or threateningly dark or obscure
dim, subdued
lacking in light; not bright or harsh
dusky, twilight, twilit
lighted by or as if by twilight
gloomful, glooming, gloomy, sulky
depressingly dark
lightless, unilluminated, unlighted, unlit
without illumination
semidark
partially devoid of light or brightness
Stygian, tenebrific, tenebrious, tenebrous
dark and gloomy
show more antonyms...

adj (used of color) having a relatively small amount of coloring agent

light blue”
light colors such as pastels”
“a light-colored powder”
Synonyms:
light-colored
white
being of the achromatic color of maximum lightness; having little or no hue owing to reflection of almost all incident light
pale
very light colored; highly diluted with white
palish
slightly pale
pastel
delicate and pale in color
powdery
as if dulled in color with a sprinkling of powder
Antonyms:
dark
(used of color) having a dark hue
black
being of the achromatic color of maximum darkness; having little or no hue owing to absorption of almost all incident light
darkish
slightly dark
show more antonyms...

adj (of sound or color) free from anything that dulls or dims

“a light lilting voice like a silver bell”
Synonyms:
clean, clear, unclouded
pure
free of extraneous elements of any kind

v make lighter or brighter

Synonyms:
illume, illuminate, illumine, light up
Types:
floodlight
illuminate with floodlights
spotlight
illuminate with a spotlight, as in the theater
Type of:
lighten, lighten up
become lighter
2

adj of comparatively little physical weight or density

“a light load”
“magnesium is a light metal--having a specific gravity of 1.74 at 20 degrees C”
Synonyms:
lightweight
weighing relatively little compared with another item or object of similar use
airy
having little or no perceptible weight; so light as to resemble air
buoyant, floaty
tending to float on a liquid or rise in air or gas
lighter-than-air
relating to a balloon or other aircraft that flies because it weighs less than the air it displaces
low-density
having low relative density or specific gravity
Antonyms:
heavy
of comparatively great physical weight or density
dense
having high relative density or specific gravity
doughy, soggy
having the consistency of dough because of insufficient leavening or improper cooking
heavier-than-air
relating to an aircraft heavier than the air it displaces
hefty
of considerable weight and size
massive
consisting of great mass; containing a great quantity of matter
non-buoyant
tending to sink in a liquid or fall in air
ponderous
having great mass and weight and unwieldiness
show more antonyms...

adj not great in degree or quantity or number

“a light sentence”
“a light accent”
“casualties were light
light snow was falling”
light misty rain”
light smoke from the chimney”
Antonyms:
heavy
unusually great in degree or quantity or number
harsh
severe
show more antonyms...

adj very thin and insubstantial

light summer dresses”
Synonyms:
thin
of relatively small extent from one surface to the opposite or in cross section

adj demanding little effort; not burdensome

light housework”
light exercise”
Synonyms:
undemanding
requiring little if any patience or effort or skill

adj of little intensity or power or force

“the light touch of her fingers”
“a light breeze”
Synonyms:
easy, gentle, soft
having little impact
Antonyms:
heavy
of great intensity or power or force
big
marked by intense physical force
show more antonyms...

adj (physics, chemistry) not having atomic weight greater than average

light water is ordinary water”
Antonyms:
heavy
(physics, chemistry) being or containing an isotope with greater than average atomic mass or weight

adj less than the correct or legal or full amount often deliberately so

“a light pound”
Synonyms:
scant, short
deficient, insufficient
of a quantity not able to fulfill a need or requirement

adj moving easily and quickly; nimble

“the dancer was light and graceful”
“walked with a light tripping step”
Synonyms:
lightsome, tripping
light-footed
(of movement) having a light and springy step

adj designed for ease of movement or to carry little weight

light aircraft”
“a light truck”
Synonyms:
light-duty
not designed for heavy work

adj of the military or industry; using (or being) relatively small or light arms or equipment

light infantry”
light cavalry”
light industry”
light weapons”
Synonyms:
light-armed, lightly-armed
armed with light weapons
Antonyms:
heavy
of the military or industry; using (or being) the heaviest and most powerful armaments or weapons or equipment

adj psychologically light; especially free from sadness or troubles

“a light heart”
Synonyms:
casual, fooling
characterized by a feeling of irresponsibility
Antonyms:
heavy
marked by great psychological weight; weighted down especially with sadness or troubles or weariness
burdensome, onerous, taxing
not easily borne; wearing
distressful, distressing, disturbing, perturbing, troubling, worrisome, worrying
causing distress or worry or anxiety
leaden, weighted
made heavy or weighted down with weariness
oppressive
weighing heavily on the senses or spirit
weighty
weighing heavily on the spirit; causing anxiety or worry
show more antonyms...

adj intended primarily as entertainment; not serious or profound

light verse”
“a light comedy”
Synonyms:
frivolous
not serious in content or attitude or behavior

adj having little importance

“losing his job was no light matter”
Synonyms:
insignificant, unimportant
devoid of importance, meaning, or force

adj silly or trivial

light banter”
Synonyms:
idle
frivolous
not serious in content or attitude or behavior

adj casual and unrestrained in sexual behavior

“he was told to avoid loose (or light) women”
Synonyms:
easy, loose, promiscuous, sluttish, wanton
unchaste
not chaste

adj easily assimilated in the alimentary canal; not rich or heavily seasoned

“a light diet”
Synonyms:
digestible
capable of being converted into assimilable condition in the alimentary canal

adj having relatively few calories

light (or lite) beer”
“lite (or light) mayonnaise”
Synonyms:
calorie-free, lite, low-cal
fat-free, fatless, nonfat
without fat or fat solids

adj marked by temperance in indulgence

“a light eater”
“a light smoker”
“ate a light supper”
Synonyms:
abstemious
temperate
not extreme in behavior

adj (of sleep) easily disturbed

“in a light doze”
“a light sleeper”
Synonyms:
wakeful
shallow
not deep or strong; not affecting one deeply

adj weak and likely to lose consciousness

“felt light in the head”
light-headed with wine”
light-headed from lack of sleep”
Synonyms:
faint, light-headed, lightheaded, swooning
ill, sick
affected by an impairment of normal physical or mental function

adj (used of vowels or syllables) pronounced with little or no stress

“a syllable that ends in a short vowel is a light syllable”
Synonyms:
unaccented, weak
unstressed
not bearing a stress or accent

adv with few burdens

“experienced travellers travel light
Synonyms:
lightly
3

v cause to start burning; subject to fire or great heat

Synonyms:
ignite
Antonyms:
blow out, extinguish, quench, snuff out
put out, as of fires, flames, or lights
Types:
show 7 types...
hide 7 types...
fire up, light up
begin to smoke
reignite
ignite anew, as of something burning
conflagrate, enkindle, inflame, kindle
cause to start burning
light up
ignite
flare up
ignite quickly and suddenly, especially after having died down
rekindle
kindle anew, as of a fire
inflame, kindle
catch fire
Type of:
burn, combust
cause to burn or combust

v begin to smoke

“After the meal, some of the diners lit up”
Synonyms:
fire up, light up
Type of:
ignite
cause to start burning; subject to fire or great heat

n a device for lighting or igniting fuel or charges or fires

“do you have a light?”
Synonyms:
igniter, ignitor, lighter
Types:
show 11 types...
hide 11 types...
cigar lighter, cigarette lighter, pocket lighter
a lighter for cigars or cigarettes
fuse, fusee, fuze, fuzee, primer, priming
any igniter that is used to initiate the burning of a propellant
friction match, lucifer, match
lighter consisting of a thin piece of wood or cardboard tipped with combustible chemical; ignites with friction
match
a burning piece of wood or cardboard
detonating fuse
a fuse containing an explosive
fusee, fuzee
a friction match with a large head that will stay alight in the wind
kitchen match
a wooden friction match that will light on any granular surface; useful to light wood or gas stoves
safety fuse
a slow-burning fuse consisting of a tube or cord filled or saturated with combustible matter; used to ignite detonators from a distance
book matches, safety match
a paper match that strikes only on a specially prepared surface
slow match
match or fuse made to burn slowly and evenly
time-fuse
a fuse made to burn for a given time (especially to explode a bomb)
Type of:
device
an instrumentality invented for a particular purpose
4

v to come to rest, settle

“Misfortune lighted upon him”
Synonyms:
alight, perch
Type of:
land, set down
reach or come to rest

v fall to somebody by assignment or lot

Synonyms:
fall
accrue, fall
come into the possession of
fall
to be given by assignment or distribution
Type of:
devolve, fall, pass, return
be inherited by

v alight from (a horse)

Synonyms:
dismount, get down, get off, unhorse
Type of:
come down, descend, fall, go down
move downward and lower, but not necessarily all the way
5

adj (used of soil) loose and large-grained in consistency

light soil”
Synonyms:
loose
not compact or dense in structure or arrangement

Sign up, it's free!

Whether you're a student, an educator, or a lifelong learner, Vocabulary.com can put you on the path to systematic vocabulary improvement.