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

On this day in 1907: The first New Year’s Eve ball – one made from iron and wood, with 100 light bulbs – was dropped from the flagpole in New York’s Times Square. —Lorenzino Estrada, The Arizona Republic, 1 Jan. 2025

The original ball was made from wood and iron and lit with 100 light bulbs. —Hannah Parry, Newsweek, 31 Dec. 2024

Built by Jacob Starr, a young immigrant metalworker, the inaugural sphere was made of iron and wood and adorned with 100 25-watt light bulbs. —Samantha Stutsman, People.com, 31 Dec. 2024

The first ball, measuring 5 feet in diameter and weighing 700 pounds, was made of iron and wood and was covered with 100 25-watt light bulbs. —Saman Shafiq, USA TODAY, 31 Dec. 2024

Word History

First Known Use

1885, in the meaning defined above

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