light bulb

\ ˈlīt-ˌbəlb How to pronounce light bulb (audio) \
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

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 The administration has revoked standards that had been scheduled to take effect this year for all light bulbs., "Correction, Jan. 3," 2 Jan. 2020 Even at the dawn of the 20th century, Christmas ornaments were powered by heat from light bulbs. Vince Guerrieri, Popular Mechanics, "‘People Are Buying Their Memories Back’: The Christmas Ornament That Time Forgot," 20 Dec. 2019 When Seppala's wife dies shortly thereafter, her demise is signified in hoary fashion by a shot of a light bulb burning out. Frank Scheck, The Hollywood Reporter, "'The Great Alaskan Race': Film Review," 24 Oct. 2019 The company is committing $25 million to energy efficiency, which extends from light bulbs to chairlifts to snow-making equipment. Judith Kohler, The Denver Post, "Three Colorado Fortune 500 companies try to turn might into right — for the environment," 13 Sep. 2019 The Department of Energy finalized a rule Wednesday that will block new federal efficiency standards for certain light bulbs from going into effect as scheduled in January. Sophie Lewis, CBS News, "Trump rolls back Obama-era regulations on energy-efficient light bulbs," 4 Sep. 2019 Reindeer and dentists, puppets and LED light bulbs, Gene Autry and General Electric—these odd pairings might not seem to have much in common. Michelle Delgado, Smithsonian Magazine, "The Magical Animation of ‘Rudolph the Red-Nosed Reindeer’," 23 Dec. 2019 The maker of light bulbs, jet engines and MRI machines is in the midst of a fragile comeback from one of the darkest periods in its 127-year history. Matt Egan, CNN, "GE hires a new CFO. Task No. 1: Shrinking a mountain of debt," 25 Nov. 2019 Shape fondant into Christmas lights using a light bulb–shaped silicon food mold. Taylor Murray, Country Living, "Retro Christmas Tree Cake," 29 Oct. 2019

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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Time Traveler for light bulb

Time Traveler

The first known use of light bulb was in 1884

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Statistics for light bulb

Last Updated

11 Jan 2020

Cite this Entry

“Light bulb.” The Dictionary, Merriam-Webster Inc., Accessed 21 January 2020.

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More Definitions for light bulb

light bulb

How to pronounce light bulb (audio)

English Language Learners Definition of light bulb

: a glass bulb or tube that produces light when it is supplied with electricity

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

More from Merriam-Webster on light bulb

Thesaurus: All synonyms and antonyms for light bulb

Comments on light bulb

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