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See also: light speed


Alternative forms[edit]


light +‎ speed



lightspeed (countable and uncountable, plural lightspeeds)

  1. The speed of light (in vacuum unless another medium is specified)
    • 1994, Ursula K. Le Guin, A Fisherman of the Inland Sea, Victor Gollancz (UK), published 1996, ISBN 0575602392, page 7:
      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.
    • 2005, W. Strawn Douglas, Oracle And Other Stories, page 134:
      He paused, then finished, “with the drive from the Linz, he can do over 500 lightspeeds to meet us.