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solar sail

noun
  1. Aerospace. a design concept for spacecraft propulsion consisting of a very thin, very large sheet of highly polished material that would be driven by the pressure of sunlight.

Origin of solar sail

First recorded in 1955–60
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
British Dictionary definitions for solar sail

solar sail

noun
  1. a device that reflects light particles from the Sun, gaining momentum in the opposite direction to propel spacecraft forwards
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
solar sail in Science

solar sail

  1. A saillike device that is made of lightweight and highly reflective material and attached to a spacecraft to harness the radiation pressure of the solar wind and light for propulsion. Also called light sail
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.