light bulb

American  

noun

1. an electric light.

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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

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Etymology

Origin of light bulb

First recorded in 1880–85

Example Sentences

Blog comment sections were notoriously dynamic, full of debate and discussion and lots of light bulb moments for writers and readers alike.

From Slate • Mar. 31, 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

Call it maturity, call it confidence, call it the light bulb going on.

From Los Angeles Times • Jul. 30, 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 pressed my face close to the window, close to the small tear in the mosquito netting that Amaka blamed for letting in every moth that flapped around the light bulb at night.

From "Purple Hibiscus" by Chimamanda Ngozi Adichie