Definition of superluminal in US English:

superluminal

adjective

Physics
  • Denoting or having a speed greater than that of light.

    • ‘Bohmian mechanics involves superluminal action-at-a-distance and thus violates the ‘locality principle’ of relativity theory.’
    • ‘For there is nor the slightest shred of evidence for random superluminal wave function collapse or quantum potentials.’
    • ‘No engine is likely to generate superluminal speeds; the laws of physics prevent us from doing that, but we will be able to go many times faster than our current propulsion methods allow.’
    • ‘And since neither astronaut can affect this superluminal point of light, it seems to me the best that they can do is to use it as a coordination signal, no different than if they both had a watch.’
    • ‘Since we cannot do this step faster than light, the quantum erasure process will not be superluminal.’

Origin

1950s: from super- ‘above’ + Latin lumen, lumin- ‘a light’ + -al.

Pronunciation

superluminal

/ˌso͞opərˈlo͞omənl/