light speed

noun

: the speed of light

Accelerating particles to near light speed, such machines are ideal for smashing them to make exotic states of matter, blast out new particles, or even search for new dimensions of space.

—Adrian Cho

also, informal : an extremely fast rate or speed

A Netflix spokesman said it was adding titles at light speed while negotiating daily with studios, which have their own strategy for dealing with online distribution.

—Josh Quittner

Examples of light speed in a Sentence

Recent Examples on the Web

But that isn't all; matter that isn't feasted upon is channeled to the poles of the black hole, from where it is blasted out as twin jets of plasma moving at near-light speed. — Robert Lea, Space.com, 7 Oct. 2026

But time moves at light speed in fashion, and the pair have already left Milan in the rearview. — Hannah Jackson, Vogue, 29 Sep. 2026

Faster-than-light spacecraft still remain science fiction, as current physics prevents objects with mass from accelerating beyond light speed. — Georgina Jedikovska, Interesting Engineering, 16 Sep. 2026

If the spaceship were going at a constant, faster-than-light speed, then another ship at rest would see two images, corresponding to two different times when light from the ship could reach them. — Matt Von Hippel, ArsTechnica, 10 Sep. 2026

Word History

First Known Use

1914, in the meaning defined above

Rhymes for light speed

• accede
• agreed
• airspeed
• alkyd
• bindweed
• chickweed
• concede
• decreed
• duckweed
• exceed
• flaxseed
• impede