Greenwich Mean Time


Green·​wich Mean Time ˈgri-nij- How to pronounce Greenwich Mean Time (audio)
-nich- How to pronounce Greenwich Mean Time (audio)
: the mean time that is associated with the prime meridian of Greenwich, England, and historically used as the prime basis of standard time throughout the world
The British traditionally used Greenwich Mean Time, calculated from the meridian running through Greenwich, a borough of London.The New York Times
Coordinated Universal Time is what used to be called Greenwich Mean Time, but the new name doesn't make it any more universal than it ever was, and it remains a time zone centered in Britain.Natalie Angier
abbreviation GMT

called also Greenwich Time

compare coordinated universal time

Examples of Greenwich Mean Time in a Sentence

Recent Examples on the Web Here's the catch, though: Amazon will drop each episode at midnight in Greenwich Mean Time (GMT), according to Decider. Olivia Evans, Women's Health, 1 Sep. 2023 The dial of the Aqua Terra titanium version renders the continents in black and gray on a titanium surface—which, like the others, is done with laser ablation—with the red London city colored by red varnish to highlight the location of Greenwich Mean Time (GMT). Carol Besler, Robb Report, 17 May 2023 Note: Dates are based on Greenwich Mean Time. Lynsey Chutel, New York Times, 9 Mar. 2023 Sailors used them to determine longitude by comparing Greenwich Mean Time and the time at the current location by reading the night sky. Carol Besler, Robb Report, 1 Mar. 2023 Pacific Time, Eastern Time, Greenwich Mean Time — and one day, perhaps, Moon Time? Denise Chow, NBC News, 27 Feb. 2023

These examples are programmatically compiled from various online sources to illustrate current usage of the word 'Greenwich Mean Time.' Any opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback about these examples.

Word History


Greenwich, England

First Known Use

1782, in the meaning defined above

Time Traveler
The first known use of Greenwich Mean Time was in 1782

Dictionary Entries Near Greenwich Mean Time

Cite this Entry

“Greenwich Mean Time.” Dictionary, Merriam-Webster, Accessed 28 Nov. 2023.

Kids Definition

Greenwich mean time

Green·​wich mean time ˈgrin-ij- How to pronounce Greenwich mean time (audio)
: the time of the meridian of Greenwich used as the basis of standard time throughout the world

called also Greenwich time

Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!