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

Many artifacts represent cutting-edge technology of the day: a substantial collection of Wright Brothers materials, Benjamin Franklin’s glass armonica, a Thomas Edison light bulb, early film projection equipment, and on and on. Peter Dobrin,, "Franklin Institute locomotive is going to perch overhead in a $6 million train room renovation," 4 June 2019 Consider light-emitting diodes, the tiny part that makes LED light bulbs illuminate and are used in many industrial settings. New York Times, "What a Trade War With China Looks Like on the Front Lines," 23 June 2018 The core product is a mobile app for iOS and Android devices, but also has active integrations with connected devices such as Nest, Sonos and Philips Hue smart light bulbs. Cherie Hu, Billboard, "Meet the 2018 Techstars Music Startups Transforming the Music Industry for Good: Exclusive," 3 May 2018 One recent project focused on 23 housing developments, and changing the light bulbs and fixtures there cost $33.2 million. The Editorial Board, WSJ, "$1,973 LEDs and the Green New Deal," 15 Feb. 2019 Only in the world of green government spending is replacing light bulbs for two grand a unit a cost-saving measure. The Editorial Board, WSJ, "$1,973 LEDs and the Green New Deal," 15 Feb. 2019 Light Bulbs Some states and jurisdictions may actually require recycling light bulbs, so check your local laws before tossing these in the trash. Alissa Katz, Good Housekeeping, "How to Dispose of Everything, Including Old Cell Phones, Mattresses, and Batteries," 8 Jan. 2019 Today they are refitted to hold electric light bulbs. Christine Van Blokland, USA TODAY, "Take Me Away: Vienna’s lush palaces and coffee houses," 21 Mar. 2018 The boy had a history of kicking holes in the wall, pulling knives and, when the family started hiding potential weapons, breaking light bulbs to get shards of glass to use to cut himself, Timion said. Alexia Elejalde-ruiz,, "10 years after federal law to protect insurance coverage of mental illness, advocates question if it's working," 5 Apr. 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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Statistics for light bulb

Last Updated

14 Jun 2019

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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


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

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Thesaurus: All synonyms and antonyms for light bulb

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