speed of light

1. 1.

   the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second

   Synonymslight speedc

   Broaderspeedconstant

Questions about speed of light

What does speed of light mean?

speed of light means "the speed at which light travels in a vacuum; the constancy and universality of the speed of light is recognized by defining it to be exactly 299,792,458 meters per second".

What is another word for speed of light?

Close synonyms include light speed, c. Each sense on this page lists its own synonyms, because a word with several meanings rarely has one substitute that works for all of them.