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noun

nucleus

NYOO-klee-uhs
noun
1
The central, positively charged part of an atom, made of protons and neutrons.
"Electrons orbit the nucleus of an atom."
2
The core part of something around which everything else is built.
"These five players formed the nucleus of the championship team."
3
The membrane-bound structure in a cell that holds its genetic material.
"Under the microscope, the cell's nucleus stained dark blue."

How to Use Nucleus

Learner’s notes

In plain EnglishThe central core of something — whether an atom, a cell, or a group.

Common pairings
atomic nucleus cell nucleus nucleus of a team

Word Forms

nuclei plural, nucleuses plural

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Electrons orbit the _____ of an atom.

Etymology

A learned borrowing from Latin nucleus, "kernel" or "core."

Rhymes for nucleus

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Definitions: FreeDict original editorial