ultrawave

From ultra- +‎ wave.

ultrawave (plural ultrawaves) (science fiction)

1. A type of radiation, often described as allowing for faster-than-light communication.
   • 1969, K[arl] H[erbert] Scheer, Walter Ernsting, translated by Wendayne Ackerman, Enterprise Stardust, London: Severn House, published 1977, →ISBN, page 28:

     There were short intervals between the reports, for ultrawaves, though traveling at the speed of light, still needed some time to span the tremendous distance.

2. A device capable of receiving or producing ultrawaves.
   • 1975, Lester del Rey, “Habit”, in Early Del Rey, Garden City, N.Y.: Doubleday & Company, Inc., →ISBN, page 41:

     Of course, the radio signals came through on the ultrawave every so often, but the pep-talk description of the thrilling contest for endurance racing didn't mean much when I put it up against the facts.

• Jesse Sheidlower, editor (2001–2024), “ultrawave, n.”, in Historical Dictionary of Science Fiction.