light speed

• Terme désignant la vitesse de la lumière dans le vide, souvent employé au sens figuré pour qualifier quelque chose d'extrêmement rapide ou à haute vitesse.

A term referring to the speed of light in a vacuum, often used figuratively to describe something extremely fast or high-speed.

1. Speed of lightC1formal

   The universal physical constant representing the maximum speed at which all energy, matter, and information in the universe can travel, approximately 299,792,458 meters per second in a vacuum.

   vitesse de la lumière

   • Nothing with mass can reach light speed according to Einstein's theory of relativity.
   • The distance to the moon is about 1.3 light-seconds at light speed.
   • Scientists measure interstellar distances in light-years, based on light speed.

2. Extremely fastB2informal

   Used informally to describe something that moves or happens with incredible speed.

   vitesse de la lumière

   • The new processor works at light speed compared to the old one.
   • She finished the race at light speed, breaking the record.
   • The internet connection here is light speed fast.