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.
According to designers, one of the biggest errors is choosing the wrong light bulb. Natasha Bazika, Martha Stewart, 14 June 2026 One of my favorite all-time estate sale finds was a huge box filled with a variety of light bulbs for $5. Jennifer Prince, Southern Living, 5 June 2026 Not every world-changing invention arrives with the fame of the light bulb or the airplane. Kaif Shaikh, Interesting Engineering, 28 May 2026 The Bitcoin Ticket Miner is a compact, fully standalone mining device that sits on your desk, draws less power than a light bulb, and quiEvery 10 minutes, the Bitcoin network awards a full block reward to a winning miner. Stackcommerce Team, PC Magazine, 26 May 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 17 Jun. 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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