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light bulb

American  

noun

  1. an electric light.


light bulb British  

noun

  1. Sometimes shortened to: bulb.  a glass bulb containing a gas, such as argon or nitrogen, at low pressure and enclosing a thin metal filament that emits light when an electric current is passed through it

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of light bulb

First recorded in 1880–85

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

"The filters would be very good insulation, and someone had a light bulb moment and probably bought this as scrap off their manager," he said.

From BBC • Mar. 25, 2026

In contrast, regulatory bodies like the FTC have been part of the federal government for longer than the light bulb.

From Slate • Dec. 11, 2025

His most recent apartment inspection failed because the light bulb in the fridge was out.

From Slate • Oct. 8, 2025

But it was a light bulb moment with the swing that made the most profound change.

From Los Angeles Times • Jun. 30, 2025

I hold the article almost on top of the light bulb.

From "The Bletchley Riddle" by Ruta Sepetys and Steve Sheinkin

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