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

Amazon Echo Sub, a subwoofer that allows for multiroom audio, will release on October 11th and cost $129.99 Amazon Echo Plus has been redesigned and includes a free Philips Hue smart light bulb as a preorder bonus. Cameron Faulkner, The Verge, "Amazon’s new Alexa-ready products are now available for preorder," 20 Sep. 2018 Make a habit of occasionally checking your brake light bulbs. Alex Leanse, Popular Mechanics, "10 Tire and Brake Problems All Drivers Need to Know," 23 Feb. 2017 There are the usual suspects: smart TVs, smart light bulbs, smart speakers, smart thermostats, smart door locks, and so on. Fox News, "10 smart devices you never knew about before now," 12 Sep. 2018 Although the event is not accepting any air conditioners, washers/dryers, refrigerators, dehumidifiers, water coolers, light bulbs, vacuums, microwaves or household batteries. Courant Community, "Community News For The Valley Edition," 8 May 2018 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

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

29 Nov 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

What made you want to look up light bulb? Please tell us where you read or heard it (including the quote, if possible).


to enclose within walls

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