prime meridian

SEE SYNONYMS FOR prime meridian ON THESAURUS.COM

noun

the meridian running through Greenwich, England, from which longitude east and west is reckoned.

Words nearby prime meridian

prime cost, prime field, prime focus, prime ideal, prime interest rate, prime meridian, prime minister, prime mover, prime number, prime number theorem, prime of life

Origin of prime meridian

First recorded in 1860–65

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2020

British Dictionary definitions for prime meridian

prime meridian

noun

the 0° meridian from which the other meridians or lines of longitude are calculated, usually taken to pass through Greenwich

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

Scientific definitions for prime meridian

prime meridian

[ prīm ]

The meridian with a longitude of 0°, adopted officially in 1884 as a reference line from which longitude east and west are measured and as a basis for standardized time zones. It passes through Greenwich, England, the site of the Royal Greenwich Observatory, which was founded in 1675 and which closed except as a museum in 1998. The prime meridian, together with its opposite meridian having a longitude of 180°, divide the Earth roughly into the Eastern and Western Hemispheres, with those portions of the British Isles, Europe, and Africa that lie west of the prime meridian, considered for practical purposes as belonging to the Eastern Hemisphere.

Cultural definitions for prime meridian

prime meridian

The meridian at zero degrees longitude. All longitude is measured relative to the prime meridian, which passes through Greenwich, England.