light up
phrasal verb
1
of a light
: to become lit : to begin shining
All of the lights on the display suddenly lit up.
—often used figuratively to express interest or pleasureHis eyes/face lit up when she walked in the room.
2
informal, of a telephone
: to show a light indicating that someone is calling
When the DJ announced a contest, the phones lit up.
3
informal
: to light a cigarette
I can't wait to light up after work.
Examples of light up in a Sentence
Recent Examples on the Web
Dense clumps of primordial hydrogen and helium left over from the big bang collapsed under their own gravitational weight, igniting thermonuclear chain reactions at their cores that would light up the universe for the first time.
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Conor Feehly, Scientific American, 4 Mar. 2025
While Léo and his pals nervously poke fun at the snogging all around them, the boy has trouble reconciling his feelings for a girl named Lucie, who makes his own lips light up like a neon flamingo.
—Peter Debruge, Variety, 2 Mar. 2025
Grade the episode in our poll, then light up the comments.
—Nick Caruso, TVLine, 21 Feb. 2025
These storms trigger interactions between the Earth’s magnetic field and charged particles from the sun, resulting in the stunning colors that light up the sky.
—Valerie Mesa, People.com, 14 Feb. 2025
See All Example Sentences for light up
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Conor Feehly, Scientific American, 4 Mar. 2025
While Léo and his pals nervously poke fun at the snogging all around them, the boy has trouble reconciling his feelings for a girl named Lucie, who makes his own lips light up like a neon flamingo.
—Peter Debruge, Variety, 2 Mar. 2025
Grade the episode in our poll, then light up the comments.
—Nick Caruso, TVLine, 21 Feb. 2025
These storms trigger interactions between the Earth’s magnetic field and charged particles from the sun, resulting in the stunning colors that light up the sky.
—Valerie Mesa, People.com, 14 Feb. 2025
See All Example Sentences for light up
Cite this Entry
“Light up.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light%20up. Accessed 18 Mar. 2025.
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