light bulb

\ˈlīt-ˌbəlb \
variants: or lightbulb

Definition of light bulb 

: an electric lamp: such as

a : one in which a filament gives off light when heated to incandescence by an electric current

called also incandescent, incandescent lamp

b : fluorescent lamp

Illustration of light bulb

Illustration of light bulb

light bulb (incandescent): 1 bulb containing gas, 2 filament, 3 connecting and supporting wires, 4 exhaust tube, 5 screw base, 6 base contact

Examples of light bulb in a Sentence

Recent Examples on the Web

And much is lost through the use of inefficient devices, like incandescent light bulbs that heat up a filament to produce light. David Roberts, Vox, "This technology could fundamentally change our relationship to electricity," 5 June 2018 To mark its first decade, the museum has switched from incandescent light bulbs to LEDs, a birthday gift from the Leonardo DiCaprio Foundation. Deborah Vankin,, "'Urban Light': Everything you didn't know about L.A.'s beloved landmark," 14 Feb. 2018 The second company — the one with the MIT pedigree — designed an Internet-connected LED light bulb. Scott Kirsner,, "Why one Boston home security startup caught on and another didn’t," 12 July 2018 The red steel pillars of the station hurtled by, and then the grotty cavern walls of the tunnel, its bare light bulbs and heavy cables telescoping past. William Finnegan, The New Yorker, "Can Andy Byford Save the Subways?," 2 July 2018 Composed of 2,500 light bulbs and 1,000 feet of neon tubing, the sign exacts a significant cost in electricity and maintenance. Ian Cummings, kansascity, "At KC’s Western Auto building, residents try to relight an iconic neon sign," 26 July 2017 Some of the repairs were things like $15 to replace a light bulb, but some of there were legitimate. George Stephens And Charles Jacobus, Houston Chronicle, "Husband in divorce process preventing home showing," 6 May 2018 Daddy was just helping mommy look for broken light bulbs,' my husband stammered. Charlotte Hilton Andersen, Redbook, "24 Cringe-Worthy Stories From Parents Whose Kids Walked In On Them Having Sex," 11 Sep. 2017 This is called incandescence and is the way a traditional light bulb generates its light. Kevin Davenport, idahostatesman, "O say can you see? The science behind the booms and blooms of Independence Day fireworks," 3 July 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'light bulb.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of light bulb

1884, in the meaning defined above

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Phrases Related to light bulb

incandescent light bulb

incandescent with rage

Statistics for light bulb

Last Updated

18 Oct 2018

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Time Traveler for light bulb

The first known use of light bulb was in 1884

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More Definitions for light bulb

light bulb


Kids Definition of light bulb

: a lamp in which a glow is produced by the heating of a wire by an electric current

Comments on light bulb

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