light bulb

noun

variants or lightbulb

ˈlīt-ˌbəlb 

plural light bulbs or lightbulbs

: 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

: one having a coating of fluorescent material on its inner surface that emits visible light : fluorescent lamp

especially : compact fluorescent light

c

: one using LEDs to generate light

Illustration of light bulb

• 1 bulb containing gas
• 2 filament
• 3 connecting and supporting wires
• 4 exhaust tube
• 5 screw base
• 6 base contact

Examples of light bulb in a Sentence

Recent Examples on the Web

This versatile light bulb integrates seamlessly with the Alexa, Google, and SmartThing ecosystems and works with a host of other smart home devices using the U home app and IFTTT applets. —PCMAG, 15 Feb. 2025

From light bulbs engineered to burn out after a specific number of hours to smartphones that slow down with new software updates, companies have mastered the art of creating products that need frequent replacement. —Vijay Govindarajan, Harvard Business Review, 18 Dec. 2024

The only means of communication the public had when trying to reach its police was a light bulb, which hung in the intersection at Main Street South and Second Avenue. —Kay Johnson, Twin Cities, 7 Feb. 2025

With more-efficient light bulbs, people may keep their lights on for longer or build things like the Sphere in Las Vegas. —Greg Rosalsky, NPR, 4 Feb. 2025

Word History

First Known Use

1885, in the meaning defined above

Rhymes for light bulb

• lightbulb

Kids Definition

lightbulb

noun

light·​bulb ˈlīt-ˌbəlb 

: an electric lamp: as

a

: one in which a filament gives off light when heated by an electric current

called also incandescent lamp

b

: fluorescent lamp