perihelion[per′ə hē′lē ən, -hēl′yən]
perihelion definition by Webster's New World
Webster's New World College Dictionary Copyright © 2010 by Wiley Publishing, Inc., Cleveland, Ohio. Used by arrangement with John Wiley & Sons, Inc.
perihelion definition by American Heritage Dictionary
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
noun pl. per·i·he·li·a
The point nearest the sun in the orbit of a planet or other celestial body.
Origin: Alteration of New Latin perihēlium : peri- + Greek hēlios, sun; see sāwel- in Indo-European roots.
- perˌi·heˈli·al adjective
perihelion - Science Definition
The point at which an orbiting object, such as a planet or a comet, is closest to the Sun. Compare aphelion, perigee.