light bulb

noun

variants or lightbulb
plural light bulbs or lightbulbs
Synonyms of light bulbnext
: 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.
People obsessively worked on light bulbs and the systems that powered them, finding little improvements year after year. Literary Hub, 8 Apr. 2026 The glitch means that drivers in the seat of a 2024 or 2025 ‘Vette wouldn’t realize if their turn signals’ light bulbs failed to turn on. Nicole Hoey, Robb Report, 6 Apr. 2026 The beetle manages to grab a leaf and right herself again before climbing its green surface to discover the call of a new light bulb. María Ospina, The Dial, 31 Mar. 2026 From here, all that’s left to pick out are the light bulbs. Audrey Lee, Architectural Digest, 31 Mar. 2026 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

Browse Nearby Words

Cite this Entry

“Light bulb.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/light%20bulb. Accessed 15 Apr. 2026.

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

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