Definition

Proper noun The Greenwich Meridian is the prime meridian of the world, defined as 0° longitude. It is the line from which all other longitudes are measured east or west. This meridian passes through the Royal Observatory in Greenwich, London, and was established as the international standard in 1884.

Usage

The term is used to specify the fundamental reference line for global navigation, cartography, and timekeeping (Greenwich Mean Time, or GMT, is based on solar time at this meridian).

Examples

• The Greenwich Meridian divides the Earth into the Eastern and Western Hemispheres.
• The conference of 1884 formally adopted the Greenwich Meridian as the prime meridian.
• Our coordinates are 15 degrees east of the Greenwich Meridian.

Advanced Usage

• The Prime Meridian: This is a common synonym for the Greenwich Meridian, emphasizing its role as the zero-longitude reference.
• In technical contexts like geodesy or astronomy, the Greenwich Meridian may be precisely defined in relation to specific celestial reference points.

Variants and Related Words

• Prime Meridian (n): Another name for the Greenwich Meridian.
• Longitude (n): The angular distance east or west from the Greenwich Meridian.
• GMT (Greenwich Mean Time) (n): The mean solar time at the Greenwich Meridian.

Synonyms

• Prime Meridian
• Zero Meridian
• Longitude Zero

Related Phrases

• East/West of Greenwich: A phrase used to describe a location's longitude.
  • The island is located 75 degrees west of Greenwich.

Noun

1. the meridian passing through Greenwich; was internationally adopted as the earth's zero of longitude in 1884