international date line

noun

: an arbitrary line approximately along the 180th meridian designated as the place where each calendar day begins

Examples of international date line in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
In Australia, near the edge of the international date line, matches are things to be watched at 3:15 A.M. or 4:45 A.M. Naaman Zhou, The New Yorker, 22 Nov. 2022 The position of the international date line meant hitting a ball into right field was hitting it into the next day. Washington Post, 30 Apr. 2022 Only in Hawaii and Midway did the vagaries of the international date line place the event on December 7. Daniel Immerwahr, The Atlantic, 4 Apr. 2022 Several hours before the attack on Pearl Harbor, which lay across the international date line, the Japanese landed on the beaches of northeastern Malaya and began a rapid advance toward Singapore. Richard Collett, Smithsonian Magazine, 28 Mar. 2022 Because of where the international date line sits, countries in Asia and the Pacific region are among the first to usher in each new year. Nick Perry, chicagotribune.com, 31 Dec. 2021

Word History

First Known Use

1875, in the meaning defined above

Time Traveler
The first known use of international date line was in 1875

Browse Nearby Words

Cite this Entry

“International date line.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/international%20date%20line. Accessed 7 Sep. 2025.

Kids Definition

international date line

noun
: an imaginary line along the 180th meridian named as the place where each calendar day begins

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