kilometer

noun

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-
: 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
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.
That crater was formed by an ancient asteroid impact and is about 93 miles (150 kilometers) in diameter. Jamie Carter, Forbes.com, 26 Apr. 2025 Dark Eagle is designed to fly at speeds exceeding Mach 5, or 3,800 mph, with a reported range of 1,725 miles (2,775 kilometers), sufficient to reach Taiwan from Guam, or NATO's borders with Russia from Western Europe. Stephen Clark, ArsTechnica, 26 Apr. 2025 The haulers would stop about ten kilometers outside the city, and there the cargo would be transferred to carts pulled by beasts of burden, a slow and arduous process that everyone had come to accept as normal. EW.com, 25 Apr. 2025 In the event of a nuclear attack, traffic would halt, and instead civilians would stream in, sealing off the tunnel entrances with the aid of four concrete doors 1.5 meters thick and capable of withstanding a nuclear detonation at a distance of 1 kilometer. Jessi Jezewska Stevens, The Dial, 24 Apr. 2025 See All Example Sentences for kilometer

Word History

Etymology

French kilomètre, from kilo- + mètre meter

First Known Use

1810, in the meaning defined above

Time Traveler
The first known use of kilometer was in 1810

Browse Nearby Words

Cite this Entry

“Kilometer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/kilometer. Accessed 30 Apr. 2025.

Kids Definition

kilometer

noun
ki·​lo·​me·​ter kə-ˈläm-ət-ər How to pronounce kilometer (audio) kil-ˈäm- How to pronounce kilometer (audio)
ˈkil-ə-ˌmēt-ər
: a metric unit of length equal to 1000 meters see metric system

Medical Definition

kilometer

noun
ki·​lo·​me·​ter
variants or chiefly British kilometre
: 1000 meters

More from Merriam-Webster on kilometer

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