GMT
Definition
- Proper Noun:
- Greenwich Mean Time: The mean solar time at the Royal Observatory in Greenwich, London, historically used as the primary global time standard from which all other time zones are calculated. It is based on the Earth's rotation relative to the sun.
- Time Standard: Although largely superseded in technical contexts by Coordinated Universal Time (UTC), "GMT" remains a common term for the time zone at zero degrees longitude (UTC+0), especially in everyday language.
Usage Examples
- Proper Noun:
- Cuộc họp trực tuyến bắt đầu lúc 14:00 GMT. (The online meeting starts at 14:00 GMT.)
- Múi giờ của Việt Nam là GMT+7. (Vietnam's time zone is GMT+7.)
- Hãy đổi giờ địa phương của bạn sang GMT. (Please convert your local time to GMT.)
Advanced Usage
- "GMT" vs. "UTC": While often used interchangeably in casual contexts, UTC is a more precise time standard regulated by atomic clocks, whereas GMT is based on astronomical observations. In practice, for most general purposes, they are considered equivalent (GMT = UTC).
- Hệ thống máy chủ của chúng tôi sử dụng UTC, nhưng bạn có thể hiểu nó là GMT. (Our server system uses UTC, but you can understand it as GMT.)
Variants and Related Words
- UTC (Coordinated Universal Time) (n): The primary time standard by which the world regulates clocks and time. It is effectively the modern successor to GMT.
- Time Zone (n): A region of the globe that observes a uniform standard time for legal, commercial, and social purposes.
Synonyms
- Greenwich Time: A less common synonym for GMT.
- Zulu Time (Z): A term used in aviation and military contexts equivalent to GMT/UTC.
Related Terms
- Longitude: The geographic coordinate that specifies the east-west position of a point on Earth's surface. The Prime Meridian (0° longitude) at Greenwich defines GMT.
- Prime Meridian: The meridian at 0° longitude, passing through Greenwich, from which longitude east and west is measured.