borough of Greater London, England, located on the prime meridian: formerly the site of an astronomical observatory
- A borough of Greater London in southeast England on the Thames River. It is the site of the original Royal Observatory, through which passes the Prime Meridian, or longitude 0°.x
- A town of southwest Connecticut on Long Island Sound. Settled in 1640, it is a wealthy suburb of New York City and home to many investment companies.x
From Old English Grenewic (“green harbor”).