nano·​sec·​ond | \ ˈna-nə-ˌse-kənd How to pronounce nanosecond (audio) , -kənt \

Definition of nanosecond

1 : one billionth of a second
2 : a very brief moment

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Did You Know?

The nonserious use of nanosecond is probably much more common than the proper technical use. In measurement terms such as nanosecond, nanogram, and nanometer, nano- means "billionth;" in other kinds of words, its meaning isn't quite so precise. In computers, the speed of reading and writing to random access memory (RAM) is measured in nanoseconds. By comparison, the speed of reading or writing to a hard drive or a CD-ROM player, or for information to travel over the Internet, is measured in milliseconds (thousandths of a second), which are a million times longer than nanoseconds.

Examples of nanosecond in a Sentence

It happens in less than a nanosecond. a nanosecond was about all that it took her to accept his marriage proposal
Recent Examples on the Web With a precision of one-quarter of 1 nanosecond, the detector counts the number of photons arriving as a function of time. Adrian Cho, Science | AAAS, "‘Time camera’ generates 3D images from echoes of light," 4 Aug. 2020 French scientists believe the world stood still for a nanosecond, causing the divergence of tidal forces. Ashley Chervinski,, "R29 Binge Club: Netflix’s Dark Final Season Recap," 28 June 2020 Many companies dumped their employees in a nanosecond. Adam Grant, The Economist, "The world after covid-19 Adam Grant on how jobs, bosses and firms may improve after the crisis," 1 June 2020 The sheer logistical challenge of creating the amount of credit the Paycheck Protection Program aims for is enormous, and the program has had to go from zero to 60 in the policy equivalent of a nanosecond. Jeff Spross, TheWeek, "What went wrong with coronavirus aid to small businesses," 7 Apr. 2020 Cash fired to Stanley, who applied the tag with a nary a nanosecond to spare. Gene Myers, Detroit Free Press, "Al Kaline's words from 1968 World Series will live forever: 'I'll never forget it'," 10 Apr. 2020 Many attribute this to automated trading strategies, and algorithms that trigger transactions in nanoseconds won’t be affected if an hour or two is cut from the trading day. New York Times, "What a ‘Wartime’ Economy Looks Like," 18 Mar. 2020 This has to happen at the nanosecond level, since the signals travel at the speed of light. Popular Science, "Self-driving cars still have major perception problems," 9 Mar. 2020 Each packet contains 110 billion protons and is spaced 25 nanoseconds apart, an interval of about 25 billionths of a second. Richard Morin, Washington Post, "At the Large Hadron Collider, a peek at the future of science," 20 Sep. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'nanosecond.' 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 nanosecond

1958, in the meaning defined at sense 1

History and Etymology for nanosecond

International Scientific Vocabulary

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Time Traveler for nanosecond

Time Traveler

The first known use of nanosecond was in 1958

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Statistics for nanosecond

Cite this Entry

“Nanosecond.” Dictionary, Merriam-Webster, Accessed 29 Oct. 2020.

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More Definitions for nanosecond


How to pronounce nanosecond (audio)

English Language Learners Definition of nanosecond

technical : one billionth of a second
: a very short time


nano·​sec·​ond | \ -ˌsek-ənd, -ənt How to pronounce nanosecond (audio) \

Medical Definition of nanosecond

: one billionth of a second abbreviation ns, nsec

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