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 But after a friend bought one of the spice mixes, a light bulb went off. Sharyn Jackson, Star Tribune, "Stock your fridge and pantry with these 12 products made by Twin Cities restaurants," 15 Jan. 2021 An hour later, the video showed another man unscrewing the light bulb. Star Tribune, "Twin Cities metro police blotter, Jan. 17," 16 Jan. 2021 Every other light bulb across a wide swath of northeastern and central Minnesota is now powered exclusively by wind, solar and hydro electricity. Brooks Johnson, Star Tribune, "Minnesota Power reaches 50% renewable energy," 16 Dec. 2020 Credit for the origins of the electric Christmas lights, which are today such an important component of Christmas trees, goes to a colleague of Thomas Edison, Edward Johnson, in 1882 — three years after the invention of the incandescent light bulb. Kevin Dayhoff,, "Dayhoff: Tracing the history of Christmas decorations in Carroll County and beyond," 4 Dec. 2020 Most early electric appliances — and Christmas lights — had a screw-in electric plug, like that of a light bulb. Kevin Dayhoff,, "Dayhoff: Tracing the history of Christmas decorations in Carroll County and beyond," 4 Dec. 2020 My friend Ally Mahoney’s mom used to ask her to come over to change a light bulb or open the lid of a stubborn jar. Karina Bland, The Arizona Republic, "Sure, mom asks for help, but readers agree the visits are about time together," 29 Oct. 2020 This light bulb moment inspired Cahn and her co-founders to launch their own crowdfunding platform, IFundWomen, with the goal to drive funding towards female entrepreneurs and close the gender funding gap in venture capital. NBC News, "Women who inspire: Entrepreneurs who are resetting amid COVID-19," 5 Oct. 2020 The 36-watt light fits in any standard light bulb socket. Billy Cadden, Popular Science, "Best gardening supplies for the horticulturally hopeless," 23 Sep. 2020

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

24 Feb 2021

Cite this Entry

“Light bulb.” Dictionary, Merriam-Webster, Accessed 8 Mar. 2021.

Style: MLA
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More Definitions for light bulb

light bulb


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

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