ki·​lo·​me·​ter | \ kə-ˈlä-mə-tər How to pronounce kilometer (audio) , ki-; ˈki-lə-ˌmē-tər How to pronounce kilometer (audio) , ˈkē-lə- \

Definition of kilometer

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

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 It’s probably not a coincidence that a precursor to Stonehenge dates to around the same time: a ring of pine posts that stood a bit more than half a kilometer away from the much later site at Stonehenge. Kiona N. Smith, Ars Technica, 4 May 2022 Each square kilometer of lake has an average of 232 lightning flashes a year, for a total of some 297 thunderstorms annually. Emily Matchar, Smithsonian Magazine, 4 Feb. 2022 In the North Sea, a kilometer below the ocean floor, the energy company Equinor has been capturing CO2 from a gas processing plant and storing a million tons of CO2 a year since 1996, avoiding Norway’s tax on CO2 releases. Klaus Lackner, The Conversation, 18 Jan. 2022 The breeding colony was discovered in February 2021 by the German polar research vessel Polarstern, which was surveying the seabed about half a kilometer below the ship. Katie Hunt, CNN, 13 Jan. 2022 Most of us will never question why a gram is a gram or a kilometer is a kilometer. Rachael Pells, Wired, 3 Jan. 2022 The result is a more flexible and performance-oriented shoe that brings it all together, balancing lightness in weight and comfort in fit that invites many an effortless kilometer — while looking great. Adam Chase, Outside Online, 26 Mar. 2021 Look at the tenth and final kilometer, on the far right. Alex Hutchinson, Outside Online, 27 Mar. 2021 The site of the Chernobyl Nuclear Power Plant in northern Ukraine has been surrounded for more than three decades by a 1,000-square-mile (2,600-square-kilometer) exclusion zone that keeps people out. Scientific American, 8 Mar. 2022 See More

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.

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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Time Traveler for kilometer

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The first known use of kilometer was in 1810

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Statistics for kilometer

Last Updated

10 May 2022

Cite this Entry

“Kilometer.” Dictionary, Merriam-Webster, Accessed 18 May. 2022.

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More Definitions for kilometer


ki·​lo·​me·​ter | \ ki-ˈlä-mə-tər How to pronounce kilometer (audio) , ˈki-lə-ˌmē-tər \

Kids Definition of kilometer

: a metric unit of length equal to 1000 meters


variants: or chiefly British kilometre \ ˈkil-​ə-​ˌmēt-​ər How to pronounce kilometer (audio) , kə-​ˈläm-​ət-​ər How to pronounce kilometer (audio) \

Medical Definition of kilometer

: 1000 meters

More from Merriam-Webster on kilometer

Nglish: Translation of kilometer for Spanish Speakers

Britannica English: Translation of kilometer for Arabic Speakers


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