Lightspeed
noun, slang ·Uncommon ·College level
Definitions
- 1 The speed of light (in vacuum unless another medium is specified). countable, uncountable
"If we're going to a world a hundred light-years from here at near lightspeed, we spend according to our own perceptions, only a few minutes doing so and arrive only a few minutes older."
- 2 An extremely fast speed. colloquial, countable, figuratively, uncountable
"In recent years, other activist terms have followed light-speed trajectories. The term “Latinx” overtook academic institutions and briefly became fashionable in the media, still prevalent in some influential publications, like The New Yorker, even though only 3 percent of Hispanics (or Latinos, if you prefer) use it."
Synonyms
All synonymsExample
More examples"If we're going to a world a hundred light-years from here at near lightspeed, we spend according to our own perceptions, only a few minutes doing so and arrive only a few minutes older."
Etymology
From light + speed.
Related phrases
More for "lightspeed"
Data sourced from Wiktionary, WordNet, CMU, and other open linguistic databases. Updated March 2026.