light bulb, lightbulb n. A glass bulb with metallic contacts on the outside connected to a wire filament (usually tungsten) inside that emits light when heated by passage of electricity through the filament; used as the replaceable light-emitting component of an electric lamp, flashlight, lighting fixture, etc.
Synonyms:light bulb, bulb, incandescent lamp, electric light, electric-light bulb.
... in Paris the taxicabs and autos rushed dangerously through streets darkened to baffle the Zeppelins. In the hotel there was little heat, only wood fires in one's room. In the homes a single electric light bulb was permitted for each room; violation of this rule meant loss of electric light from that apartment ... — Face to Face with Kaiserism • James W. Gerard
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