quantum number
noun
: any of a set of numbers that indicate the magnitude of various discrete quantities (such as electric charge) of a particle or system and that serve to define its state
Examples of quantum number in a Sentence
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The energy state of an atom is denoted by its principal quantum number, designated n, which defines the probability of finding an electron at a particular distance from the nucleus.
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Jeanna Bryner, Scientific American, 20 Jan. 2026
Middle Sister prattled on about how an atom having six principal quantum numbers can yield several emission lines, or some such.
—Chicago Tribune, chicagotribune.com, 2 June 2018
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Jeanna Bryner, Scientific American, 20 Jan. 2026
Middle Sister prattled on about how an atom having six principal quantum numbers can yield several emission lines, or some such.
—Chicago Tribune, chicagotribune.com, 2 June 2018
Cite this Entry
“Quantum number.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/quantum%20number. Accessed 14 Feb. 2026.
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