relativistic

American  

[rel-uh-tuh-vis-tik] / ˌrɛl ə təˈvɪs tɪk /

adjective

1. of or relating to relativity or relativism.

2. Physics.

   1. subject to the special or the general theory of relativity.

   2. (of a velocity) having a magnitude that is a significant fraction of the speed of light.

   3. (of a particle) having a relativistic velocity.

      radiation from relativistic electrons.

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relativistic British  

/ ˌrɛlətɪˈvɪstɪk /

adjective

1. physics having or involving a speed close to that of light so that the behaviour is described by the theory of relativity rather than by Newtonian mechanics

   a relativistic electron

   a relativistic velocity

2. physics of, concerned with, or involving relativity

3. of or relating to relativism

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Other Word Forms

• relativistically
  adverb
• ultrarelativistic
  adjective
• unrelativistic
  adjective

Etymology

Origin of relativistic

First recorded in 1885–90; relativist + -ic

Example Sentences

The new work addresses this limitation by introducing the first fully relativistic framework for a wide range of possible environments.

From Science Daily • Dec. 19, 2025

Their picture shows the galaxy NGC 5128 and its relativistic jet - beams of radiation and particles travelling close to the speed of light.

From BBC • Sep. 12, 2024

In particular, Webb highlights what is known as synchrotron radiation: emission produced from charged particles, like electrons, moving around magnetic field lines at relativistic speeds.

From Science Daily • Oct. 30, 2023

On the other end of the spectrum, hot dark matter moves at relativistic speeds, rendering it incapable of gathering most anything.

From Scientific American • Jun. 20, 2023

In truth, there was no doubt that a relativistic limit to cyclotron energies existed; the question was where it was.

From "Big Science" by Michael Hiltzik