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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Using these new attosecond X-ray laser pulses could allow scientists to study the fastest processes in materials at the atomic-length scale and to discern different elements.
—Thomas Linker, The Conversation, 15 Oct. 2025
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
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Thomas Linker, The Conversation, 15 Oct. 2025
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
See All Example Sentences for attosecond
Cite this Entry
“Attosecond.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/attosecond. Accessed 24 Oct. 2025.
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