Definition of "light-year" []

• The distance that light travels in a vacuum in one year, approximately 9.46 trillion (9.46 × 1012) kilometers or 5.88 trillion (5.88 × 1012) miles. (noun)
• Informal A long way. Often used in the plural: a small town light-years away from the action of the capital. (noun)

American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

• "Because the distances in space are so vast, scientists use a unit called the light-year to measure them."
• "They think nothing of jaunting off on ten thousand plus light-year journeys, expecting to meet up again eons in the future with nary a hiccup (except, of course, for the events in the story)."
• "It's ironic that Sylvia Hermon (by a small light-year the nicest, most liberal, most intelligent and best intentioned of the NI MPs) is also the "cheapest"."