light bulb

noun

variants or lightbulb
plural light bulbs or lightbulbs
: 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
: one having a coating of fluorescent material on its inner surface that emits visible light : fluorescent lamp
c
: 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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Old and extra light bulbs seem to always end up in a box on a garage shelf, wasting storage space that could be used for other items. Maria Sabella, Better Homes & Gardens, 12 July 2025 Keep Light Bulbs From Sticking Outdoor light bulbs can have a knack for sticking in the socket after long periods of time, leaving you with the task of trying to unscrew a stubborn bulb without breaking the glass. Kaitlyn Yarborough, Southern Living, 21 June 2025 The Shiloh lamp is also compatible with dimmable light bulbs for a more customizable glow. Kate McGregor, Architectural Digest, 20 June 2025 The light bulb moment for Fleck was when both her professional and personal experiences showed her what validation can do. Bruce Y. Lee, Forbes.com, 26 May 2025 See All Example Sentences for light bulb

Word History

First Known Use

1885, in the meaning defined above

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

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Cite this Entry

“Light bulb.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light%20bulb. Accessed 19 Jul. 2025.

Kids Definition

lightbulb

noun
light·​bulb ˈlīt-ˌbəlb How to pronounce lightbulb (audio)
: an electric lamp: as
a
: 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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