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

By incorporating their relativistic model into modern gravitational waveform calculations, the researchers demonstrate that such dark matter structures would leave distinct, measurable signatures in the signals detected by future observatories.

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

What allows the conservation of momentum are relativistic effects.

From Science Daily • Oct. 20, 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 fact, Bethe declared, thirty-four-inch pole faces were “ample” to reach the relativistic energy limit.

From "Big Science" by Michael Hiltzik