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English definition of “nucleus”

nucleus

noun [C]     /ˈnjuː.kli.əs/ US  /ˈnuː-/ (plural nuclei or nucleuses)
specialized physics the central part of an atom, usually made up of protons and neutronsCellsAtoms, molecules and sub-atomic particles specialized biology the part of a cell that controls its growth: DNA is stored in the nucleus of a cell.CellsAtoms, molecules and sub-atomic particles the nucleus of sth the group of people or things that are the most important part of something: These three players will form the nucleus of a revised and stronger team.Important and essential thingsInformation and messages
(Definition of nucleus noun from the Cambridge Advanced Learner's Dictionary & Thesaurus © Cambridge University Press)
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