variants:
or lightbulb
Definition of light bulb
: 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
: fluorescent lamp
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Merriam-Webster unabridged
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Time Traveler for light bulb
The first known use of light bulb was in 1884
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