Dictionary.com
definitions
  • synonyms

apparent time

See more synonyms on Thesaurus.com
noun
  1. Astronomy. local time measured by the hour angle of the sun.
Show More

Origin of apparent time

First recorded in 1685–95
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

apparent time in Science

apparent time

  1. Solar time as measured by the Sun's actual position with respect to an observer's local meridian and equal for any observer to the hour angle of the Sun at that location. Sundials register apparent time, which differs continuously with the observer's longitude and is not standardized across a time zone. Each degree of longitude represents a difference of four minutes in apparent time. Because of irregularities in Earth's orbit and the tilt of its axis, a day as measured by apparent time varies somewhat in length throughout the year. Also called apparent solar time♦ The moment when the Sun crosses an observer's local meridian is called the apparent noon. Compare local mean time. See more at mean time solar time.
Show More
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.