nucleusnounmasculine/ˈnu.kle.u/mediumnú·cle·oPortuguesEnglishEspanolFrancaisDefinitionThe central or most important part of something.The nucleus of the cell is essential.The nucleus of the problem is the lack of communication.syncorecenterEtymologyDo grego 'nukleon'Related wordsnuclearnúcleo celular