international date line


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

Example Sentences

Recent Examples on the Web 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 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 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 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 The volcano is located about 40 miles north of Tonga’s main island of Tongatapu near the international date line. Washington Post, 15 Jan. 2022 Some maps blow continents way out of proportion; others misleadingly split the world in half at the international date line and put Hawaii on one side and Japan on the other, as if the two islands aren't only half an ocean apart. Rasha Aridi, Smithsonian Magazine, 4 Jan. 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,, 31 Dec. 2021 This was the period when the international date line was established and when time zones were instituted. Joe Pinsker, The Atlantic, 16 Nov. 2021 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'international date line.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

Word History

First Known Use

1875, in the meaning defined above

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

Dictionary Entries Near international date line

Cite this Entry

“International date line.” Dictionary, Merriam-Webster, Accessed 2 Dec. 2022.

Kids Definition

international date line


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

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