kilometer

noun
ki·​lo·​me·​ter | \kə-ˈlä-mə-tər, ki-;ˈki-lə-ˌmē-tər \

Definition of kilometer 

: a metric unit of length equal to 1000 meters — see Metric System Table

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How do you pronounce kilometer?: Usage Guide

In North American speech kilometer is most often pronounced with primary stress on the second syllable. This pronunciation is also heard frequently in British speech. Those who object to second syllable stress say that the first syllable should be stressed in accord with the stress patterns of centimeter, millimeter, etc. However, the pronunciation of kilometer does not parallel that of other metric compounds. From 1828 to 1841 Noah Webster indicated only second syllable stress, and his successor added a first syllable stress variant in the first Merriam-Webster dictionary of 1847. Thus, both pronunciations are venerable. Most scientists use second syllable stress, although first syllable stress seems to occur with a higher rate of frequency among scientists than among nonscientists.

Did You Know?

A kilometer is equal to about 62/100 of a mile, and a mile is equal to about 1.61 kilometers. The U.S. has been slow to adopt metric measures, which are used almost everywhere else in the world. Though our car speedometers are often marked in both miles and kilometers, the U.S. and Great Britain are practically the only developed nations that still show miles rather than kilometers on their road signs. But even in the U.S., footraces are usually measured in meters or kilometers, like the Olympic races. Runners normally abbreviate kilometer to K: "a 5K race" (3.1 miles), "the 10K run" (6.2 miles), and so on.

Examples of kilometer in a Sentence

Recent Examples on the Web

Completed in 2010, the IceCube neutrino detector snares these elusive particles in a cubic kilometer of Antarctic ice. Daniel Clery, Science | AAAS, "Ghostly particle caught in polar ice ushers in new way to look at the universe," 12 July 2018 IceCube, an international observatory run by 300 scientists from 12 countries, consists of more than 5,000 sensitive photomultiplier tubes embedded in grid encompassing a cubic kilometer of ice at the South Pole. Dennis Overbye, New York Times, "It Came From a Black Hole, and Landed in Antarctica," 12 July 2018 Composed of more than 5,000 sensors embedded in a cubic kilometer of ice sitting deep beneath the Antarctic surface, IceCube picks up the flashes of blue light caused by secondary particles after a neutrino makes contact. Amina Khan, latimes.com, "After years of searching, scientists finally trace high-energy neutrinos to a distant blazar," 12 July 2018 According to Mashable, Fries and his team had identified the meteorite fall area to one square kilometer of ocean that went about 100 meters deep, then went exploring on the Nautilus, an Ocean Exploration Trust vessel. Laura Yan, Popular Mechanics, "Scientists May Have Found Meteorite Fragments in the Ocean," 8 July 2018 Rescuers led by elite navy divers have been frustrated by incessant rain and flooding that has slowed their search of the kilometers-long (miles-long) underground complex. Fox News, "Spirit of mythical princess looms over Thai cave crisis," 28 June 2018 Rescuers led by elite navy divers have been frustrated by incessant rain and flooding that has slowed their search of the kilometers-long (miles-long) underground complex. Washington Post, "Spirit of mythical princess looms over Thai cave crisis," 27 June 2018 The world’s fastest hunter—the peregrine falcon—snatches prey out of the sky at speeds of more than 300 kilometers per hour. Katie Langin, Science | AAAS, "Peregrine falcons maneuver best when dive-bombing at more than 300 kilometers per hour," 12 Apr. 2018 With so many hazards and intersections on the route, the speed limit at the site is about 20 to 25 kilometers an hour. Kyunghee Park, Bloomberg.com, "Singapore Built a Dedicated Town for Self-Driving Buses," 4 June 2018

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

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First Known Use of kilometer

1810, in the meaning defined above

History and Etymology for kilometer

French kilomètre, from kilo- + mètre meter

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Statistics for kilometer

Last Updated

10 Nov 2018

Look-up Popularity

Time Traveler for kilometer

The first known use of kilometer was in 1810

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More Definitions for kilometer

kilometer

noun

English Language Learners Definition of kilometer

: a unit of length equal to 1,000 meters

kilometer

noun
ki·​lo·​me·​ter | \ki-ˈlä-mə-tər, ˈki-lə-ˌmē-tər\

Kids Definition of kilometer

: a metric unit of length equal to 1000 meters

kilometer

noun
ki·​lo·​me·​ter
variants: or chiefly British kilometre \ ˈkil-​ə-​ˌmēt-​ər , kə-​ˈläm-​ət-​ər \

Medical Definition of kilometer 

: 1000 meters

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Comments on kilometer

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