time zone

American  

noun

1. one of the 24 regions or divisions of the globe approximately coinciding with meridians at successive hours from the observatory at Greenwich, England.

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time zone British  

noun

1. a region throughout which the same standard time is used. There are 24 time zones in the world, demarcated approximately by meridians at 15° intervals, an hour apart See also zonetime

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time zone Scientific  

1. Any of the 24 divisions of the Earth's surface used to determine the local time for any given locality. Each zone is roughly 15° of longitude in width, with local variations for economic and political convenience. Local time is one hour ahead for each time zone as one travels east and one hour behind for each time zone as one travels west. The International Meridian Conference in 1884 established the prime meridian as the starting point for the 24 zones.

2. See more at International Date Line standard time

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Etymology

Origin of time zone

First recorded in 1880–85

Example Sentences

See Examples For:

time zone

That caffeine reference was perhaps as much to the time zone, as nod to the city's famous café culture.

From BBC ● Sep. 9, 2026

For some it was before sunrise; others stayed up well past midnight in their time zone.

From Salon ● Aug. 24, 2026

When I was back East, we’d be in the same time zone and FaceTime eight hours a night, talking until we could barely keep our eyes open.

From Los Angeles Times ● Aug. 21, 2026

New employees complete a questionnaire that asks how they work best, including their time zone, peak work hours and what times of day they’re most distracted.

From The Wall Street Journal ● Jun. 10, 2026

Laleh finally tired out at about midnight Portland time, though I had no idea what the local time was, or even what time zone we were in.

From "Darius the Great Is Not Okay" by Adib Khorram