- 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 effect of light falling on an object or scene as represented in a picture.
- one of the brightest parts of a picture.
- Also called day. one compartment of a window or window sash.
- a window, especially a small one.
adjective, light·er, light·est.
verb (used with object), light·ed or lit, light·ing.
verb (used without object), light·ed or lit, light·ing.
- 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.
Origin of light1
British Dictionary definitions for light up (1 of 4)
British Dictionary definitions for light up (2 of 4)
British Dictionary definitions for light up (3 of 4)
- illumination from the sun during the day; daylight
- the time this appears; daybreak; dawn
- the act of igniting or kindling something, such as a cigarette
- something that ignites or kindles, esp in a specified manner, such as a spark or flame
- something used for igniting or kindling, such as a match
- the effect of illumination on objects or scenes, as created in a picture
- an area of brightness in a picture, as opposed to shade
- to gain sudden insight into or understanding of something
- to experience a religious conversion
- to come into being
- to come to public notice
- (verb) to ignite something, esp a match, by friction
- (interjection) British an exclamation of surprise
verb lights, lighting, lighted or lit (lɪt)
Word Origin for light
British Dictionary definitions for light up (4 of 4)
- designed to carry light loads
- not loaded
- (of a bid) made on insufficient values
- (of a player) having failed to take sufficient tricks to make his contract
verb lights, lighting, lighted or lit (lɪt) (intr)
Word Origin for light
Medicine definitions for light up
Science definitions for light up
Culture definitions for light up
Idioms and Phrases with light up (1 of 2)
Become or cause to become more animated or cheerful, as in Her laughter lit up the whole room, or His face lit up when he saw her. This expression transfers physical illumination to human moods. Also see lighten up. [Mid-1700s]
Start smoking a cigar, cigarette, or pipe, as in The minute he got outside the church he lit up. [Colloquial; mid-1800s]
Idioms and Phrases with light up (2 of 2)
In addition to the idioms beginning with light
- light a fire under
- light as a feather
- light at the end of the tunnel
- light dawned, the
- lighten up
- light heart
- light into
- lightning never strikes twice in the same place
- light on
- light out
- light up
- begin to see daylight (see the light of day)
- bring to light
- come to light
- go light on
- green light
- heavy (light) heart
- hide one's light
- in a good (bad) light
- in the cold light of day
- in the light of
- lace (light) into
- leading light
- make light of
- many hands make light work
- once over lightly
- out cold (like a light)
- see the light
- shed light on
- sweetness and light
- travel light
- trip the light fantastic