equation of time

American

noun

Astronomy.

apparent time minus mean solar time, ranging from minus 14 minutes in February to over 16 minutes in November.

equation of time British

noun

the difference between apparent solar time and mean solar time, being at a maximum in February (over 14 minutes) and November (over 16 minutes)

"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

Etymology

Origin of equation of time

First recorded in 1720–30

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

But the boring dystopia meme reminds us the end could arrive quietly but corrosively, with a total erosion of work-life balance, crowdfunding for necessary healthcare, infantilisation by technology and the equation of time with capital.

From The Guardian • Aug. 6, 2018

This difference between GMT and solar time is called "the equation of time" by astronomers.

From BBC • Dec. 20, 2014

It differs from apparent noon by the amount of the equation of time for that date.

From The Sailor's Word-Book An Alphabetical Digest of Nautical Terms, including Some More Especially Military and Scientific, but Useful to Seamen; as well as Archaisms of Early Voyagers, etc. by Belcher, Edward, Sir

This equation of time, with the sign showing in which way it is to be applied, is given for any minute of any day in the column marked "Equation of Time."

From Lectures in Navigation by Draper, Ernest Gallaudet

He appears to have been the first to understand the theory of the equation of time.

From Essays by Ralph Waldo Emerson by Turpin, Edna Henry Lee

Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023