- a unit of length, the common measure of distances equal to 1000 meters, and equivalent to 3280.8 feet or 0.621 mile. Abbreviation: km
Also especially British, kil·o·me·tre.
Origin of kilometer
The usual pronunciation for units of measurement starting with kilo-, as kilocalorie, kiloliter, and kilohertz, as well as for units of length ending in the base word meter, as centimeter, hectometer, and millimeter, gives primary stress to the first syllable and secondary to the third. It would seem logical for kilometer to follow this pattern, and in fact the pronunciation [kil-uh-mee-ter] /ˈkɪl əˌmi tər/ has been used since the early 1800's. A second pronunciation: [ki-lom-i-ter] /kɪˈlɒm ɪ tər/, with stress on the second syllable only, was first recorded in America before 1830. Although often criticized on the basis of analogy, this pronunciation has persisted in American English, increasing in frequency, and has gained popularity in British English as well. It is reinforced by words for instruments (rather than units) of measurement ending in -meter, as thermometer, barometer, and speedometer, having stress on the -om syllable. Both pronunciations are used by educated speakers, including members of the scientific community.
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018
Examples from the Web for kilometers
The Kremlin is far away—almost 1,000 kilometers away, in fact.Russia’s Freest Website Now Lives in Latvia
November 29, 2014
The shudder of the fighting could be felt 16 kilometers away.Kobani Still Stands Against ISIS and All Odds. But for How Long?
October 12, 2014
A control group—a population of gorillas unaffected by Ebola, separated by a river and 20 kilometers—was also observed.How Gorillas Are Outsmarting Ebola
September 1, 2014
A senior administration official described it as “a multi-pronged attack across hundreds of kilometers in northern Iraq.”Obama’s Iraq Plan Has a Killer Flaw—and Airstrikes Alone May Not Save It
August 8, 2014
On the outskirts of Slovyansk, a hundred kilometers away, frustration is building among some of the townsfolk.Inside East Ukraine’s Make-Believe Republics
May 15, 2014
How much time do we need and how much energy for only four thousand kilometers?Operation Earthworm
He had seven hours to go and he was still at least 16 kilometers from Rathole.
He had driven at least eight kilometers before he realized that the crack was narrowing.
But that star is only forty kilometers—or less than twenty-five miles in diameter!Islands of Space
John W Campbell
These stables were about two kilometers from the battery billets.The Delta of the Triple Elevens
William Elmer Bachman
Word Origin and History for kilometers
Online Etymology Dictionary, © 2010 Douglas Harper
- A unit of length in the metric system equal to 1,000 meters (0.62 mile). See Table at measurement.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
The New Dictionary of Cultural Literacy, Third Edition Copyright © 2005 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.