prime meridian


: the meridian of 0 degrees longitude which runs through the original site of the Royal Observatory at Greenwich, England, and from which other longitudes are reckoned

Examples of prime meridian in a Sentence

Recent Examples on the Web Weir was front and center, a human prime meridian, both timeless and untethered from today’s world, a 49er who had discovered the secrets of the cosmos inside Terrapin Station. Jeff Weiss, Spin, 21 Aug. 2023 Longitude measure distances from the prime meridian. Caroline Picard, Good Housekeeping, 31 Aug. 2018

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

Word History

First Known Use

1884, in the meaning defined above

Time Traveler
The first known use of prime meridian was in 1884

Dictionary Entries Near prime meridian

Cite this Entry

“Prime meridian.” Dictionary, Merriam-Webster, Accessed 27 Feb. 2024.

Kids Definition

prime meridian

: the meridian of 0° longitude from which other longitudes are calculated

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