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nuclei

American  
[noo-klee-ahy, nyoo-] / ˈnu kliˌaɪ, ˈnyu- /

noun

  1. plural of nucleus.


nuclei British  
/ ˈnjuːklɪˌaɪ /

noun

  1. a plural of nucleus

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of nuclei

< Latin nucleī, nominative plural of nucleus; see nucleus

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

If the atomic nuclei in a lump of iron were scaled up to human size, for instance, how far apart would they be from each other?

From The Wall Street Journal • May 15, 2026

They also contributed to important measurements involving proton and helium fluxes and helped analyze carbon nuclei data.

From Science Daily • May 14, 2026

"This brings us closer to answering deep, fundamental questions about how matter acquires mass, as well as how the vacuum structure changes inside atomic nuclei."

From Science Daily • Apr. 25, 2026

The excitation spectrum of the carbon nucleus measured in the experiment shows patterns consistent with the formation of η′-mesic nuclei.

From Science Daily • Apr. 25, 2026

When neutrons fly away from one fuel rod, the surrounding water slows them to the optimal speed before they reach the next uranium nuclei, making them more likely to create fission.

From "Meltdown" by Deirdre Langeland

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