attosecond
noun
at·to·sec·ond
ˈa-(ˌ)tō-ˌse-kənd 
-kənt
: one quintillionth (10−18) of a second
An attosecond is to a second what a second is to the age of the universe.—
IEEE Spectrum
IEEE SpectrumExamples of attosecond in a Sentence
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Then, in 2023, the Physics Nobel went to the science of attosecond spectroscopy, which also relies on applications of lasers.
—Ethan Siegel, Big Think, 7 Aug. 2025
An attosecond is a billionth of a billionth of a second.
—IEEE Spectrum, 28 May 2024
The shortest pulses produced today are only a few dozen attoseconds long.
—Will Sullivan, Smithsonian Magazine, 4 Oct. 2023
One attosecond is one-quintillionth of a second, or 0.000000000000000001 seconds.
—Charlie Wood, Quanta Magazine, 3 Oct. 2023
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Ethan Siegel, Big Think, 7 Aug. 2025
An attosecond is a billionth of a billionth of a second.
—IEEE Spectrum, 28 May 2024
The shortest pulses produced today are only a few dozen attoseconds long.
—Will Sullivan, Smithsonian Magazine, 4 Oct. 2023
One attosecond is one-quintillionth of a second, or 0.000000000000000001 seconds.
—Charlie Wood, Quanta Magazine, 3 Oct. 2023
See All Example Sentences for attosecond
Cite this Entry
“Attosecond.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/attosecond. Accessed 18 Sep. 2025.
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