nucleus /ˈnuːklijəs/ noun plural nuclei /ˈnuːkliˌaɪ/ also nucleuses plural nuclei /ˈnuːkliˌaɪ/ also nucleuses Learner's definition of NUCLEUS
[count]
1
biology : the central part of most cells that contains genetic material and is enclosed in a membrane细胞核
2
physics : the central part of an atom that is made up of protons and neutrons核；原子核
3
: a central or most important part of something核心；中心 —
usually + of