Definition of nucleus in English:
noun (plural nuclei /-lɪʌɪ/)
1The central and most important part of an object, movement, or group, forming the basis for its activity and growth: the nucleus of a British film-producing industry
More example sentences
- If this proposal is accepted, the government together with the St Lucian organizations could have an extension of the mission in Brooklyn and an important nucleus for the St Lucian community.
- The nucleus of the global movement against injustice will not - cannot, should not - be found in the centers of global privilege.
- And at the moment there is not even the nucleus of a movement to achieve that.
1.1 Physics The positively charged central core of an atom, consisting of protons and neutrons and containing nearly all its mass.
- The harmless radio waves excite protons that form the nuclei of hydrogen atoms in the body.
- Electrons produce a small magnetic field as they spin and orbit the nucleus of an atom.
- Electrons are found in clouds that surround the nucleus of an atom.
1.2 Biology A dense organelle present in most eukaryotic cells, typically a single rounded structure bounded by a double membrane, containing the genetic material.
- Dense granules surrounding the nucleus are probably cytoplasmic organelles.
- The cells had round or oval vesicular nuclei with multiple prominent nucleoli.
- The cells were characterized by large vesicular nuclei with single large nucleoli.
1.3 Anatomy A discrete mass of grey matter in the central nervous system.
- Axons travel from the neurons located in nuclei within the brain stem via the cranial nerves without synaptic interruption to the motor end plates on the striated muscle.
- These effects are produced by fibres projecting from the hypothalamus to parasympathetic nuclei in the brain stem, and to sympathetic centres in the spinal cord.
- The trochlear nerve nuclei are located ventral to the mesencephalic aqueduct.
early 18th century: from Latin, literally 'kernel, inner part', diminutive of nux, nuc- 'nut'.