light bulb


variants or lightbulb
plural light bulbs or lightbulbs
: an electric lamp: such as
: one in which a filament gives off light when heated to incandescence by an electric current

called also incandescent, incandescent lamp

: one having a coating of fluorescent material on its inner surface that emits visible light : fluorescent lamp
: one using LEDs to generate light

Illustration of light bulb

Illustration of light bulb
  • 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 For instance, in 2007, the Energy Independence and Security Act set a lumens per watt standard for light bulbs that effectively banned the incandescent-type bulb. IEEE Spectrum, 10 Feb. 2024 Let the light bulb brighten as your path is revealed and your genius creates a masterpiece on Earth! Philip Wolf, Rolling Stone, 31 Jan. 2024 To avoid decision paralysis, start with smaller products, such as smart plugs and smart light bulbs. Bret Jordan, Forbes, 28 Nov. 2023 Tell me what the conversation was like between you and Larry when the light bulb went off. Jackie Strause, The Hollywood Reporter, 4 Feb. 2024 Bridging the stories are interludes during which the koto weaves its spell while a small white butterfly (with light bulb attached) flutters about. Rob Hubbard, Twin Cities, 21 Jan. 2024 And what with food-delivery apps, Wordle, OnlyFans, long-life light bulbs, fancy home-security systems, Medicare, Uber, and so much content to watch online, the benefits of growing old together, in many people’s judgment, no longer outweigh the drawbacks. TIME, 26 Dec. 2023 When these actions were ranked by their actual impact on emissions, recycling was third-from-bottom and low-energy light bulbs were last. Matt Reynolds, WIRED, 29 Dec. 2023 Behind her, a door flanked by two light bulbs, red and green, on top. Hazlitt, 16 Nov. 2023 See More

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'light bulb.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History

First Known Use

1885, in the meaning defined above

Time Traveler
The first known use of light bulb was in 1885

Dictionary Entries Near light bulb

Cite this Entry

“Light bulb.” Dictionary, Merriam-Webster, Accessed 2 Mar. 2024.

Kids Definition


light·​bulb ˈlīt-ˌbəlb How to pronounce lightbulb (audio)
: an electric lamp: as
: one in which a filament gives off light when heated by an electric current

called also incandescent lamp

More from Merriam-Webster on light bulb

Last Updated: - Updated example sentences
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