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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.

If there had been a light bulb over his head, it would have lit up.

From Literature

“I love watching the light bulb go off, watching them be inspired,” Gill said.

From Los Angeles Times

I think it’s just cool to see how people’s brains work and what makes the light bulb go off at certain moments.

From Los Angeles Times

The 17 rare earths are found in a wide variety of everyday and high-tech devices, from light bulbs to guided missiles.

From Barron's

“That’s when the light bulb went off for me. Why not bring some of these beautiful plants from the hills into our yard?”

From Los Angeles Times