universal time

American  

noun

1. (often initial capital letters) Greenwich Time. UT

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universal time British  

noun

1.  UT.  (from 1928) name adopted internationally for Greenwich Mean Time (measured from Greenwich midnight), now split into several slightly different scales, one of which (UT1) is used by astronomers

2.  UTC.  Also called: universal coordinated time.  An internationally agreed system for civil timekeeping introduced in 1960 and redefined in 1972 as an atomic timescale. Available from broadcast signals, it has a second equal to the International Atomic Time (TAI) second, the difference between UTC and TAI being an integral number of seconds with leap seconds inserted when necessary to keep it within 0.9 seconds of UT1

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universal time Scientific  

1. The mean time for the meridian at Greenwich, England (0° longitude), which runs through the former site of the Royal Observatory. It is based on the sidereal period of Earth's rotation and is used as a basis for calculating standard clock time throughout most of the world.

2. Also called Greenwich Mean Time

3. Compare coordinated universal time

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universal time Cultural  

1. The measure of time obtained from the rotation of the Earth, also known as Greenwich mean time, after the Greenwich Observatory in England. The world's time standard today is Coordinated Universal Time, which is kept by atomic clocks. The two universal times are kept in synchronization by the occasional insertion of leap seconds into the year.

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Etymology

Origin of universal time

First recorded in 1885–90

Example Sentences

Spring cleaning has become a universal time to declutter our lives, chucking everything we no longer need.

From Salon • Apr. 5, 2024

Each lunar mission uses its own timescale that is linked, through its handlers on Earth, to coordinated universal time, or UTc — the standard against which the planet’s clocks are set.

From Scientific American • Jan. 26, 2023

Although B.I.P.M. is responsible for universal time, the International Telecommunication Union, or I.T.U., is responsible for transmitting it.

From New York Times • Nov. 19, 2022

While there’s no universal time frame for how long you should text someone before scheduling a first date, Hoffman suggests one week.

From Los Angeles Times • Oct. 24, 2022

What we want is longitude for ordinary purposes, and on that hangs the reckoning of universal time, which, of course, should be for the general use of the whole world.

From International Conference Held at Washington for the Purpose of Fixing a Prime Meridian and a Universal Day. October, 1884. Protocols of the Proceedings by Various