nucleus

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nu·cle·us

 (no͞o′klē-əs, nyo͞o′-)
n. pl. nu·cle·i (-klē-ī′) or nu·cle·us·es
1. A central or essential part around which other parts are gathered or grouped; a core: the nucleus of a city.
2. Something regarded as a basis for future development and growth; a kernel: a few paintings that formed the nucleus of a great art collection.
3. Biology A membrane-bound organelle within a eukaryotic cell that contains most of the cell's genetic material. DNA transcription takes place in the nucleus.
4. Anatomy A group of specialized nerve cells or a localized mass of gray matter in the brain or spinal cord.
5. Physics The positively charged central region of an atom, composed of protons and neutrons, about which negatively charged electrons orbit. Extremely small and dense, the nucleus contains almost all of the mass of an atom.
6. Chemistry A group of atoms bound in a structure, such as a benzene ring, that is resistant to alteration in chemical reactions.
7. Astronomy
a. The central, often brightest part of the head of a comet.
b. The solid part of a comet, composed of ice and smaller amounts of dust and rock.
c. The central, often brightest part of a galaxy.
8. Meteorology A particle on which water vapor molecules accumulate in free air to form a droplet or ice crystal.
9. Linguistics The part of a syllable having the greatest sonority. In the word middlemost (mĭd′l-mōst′) the nuclei of the three syllables are (ĭ), (l), and (ō); in the Czech word krk ("neck"), the nucleus is (r).

[Latin nuculeus, nucleus, kernel, from nucula, little nut, diminutive of nux, nuc-, nut.]

nucleus

(ˈnjuːklɪəs)
n, pl -clei (-klɪˌaɪ) or -cleuses
1. a central or fundamental part or thing around which others are grouped; core
2. a centre of growth or development; basis; kernel: the nucleus of an idea.
3. (Biology) biology (in the cells of eukaryotes) a large compartment, bounded by a double membrane, that contains the chromosomes and associated molecules and controls the characteristics and growth of the cell
4. (Anatomy) anatomy any of various groups of nerve cells in the central nervous system
5. (Astronomy) astronomy the central portion in the head of a comet, consisting of small solid particles of ice and frozen gases, which vaporize on approaching the sun to form the coma and tail
6. (General Physics) physics the positively charged dense region at the centre of an atom, composed of protons and neutrons, about which electrons orbit
7. (Chemistry) chem a fundamental group of atoms in a molecule serving as the base structure for related compounds and remaining unchanged during most chemical reactions: the benzene nucleus.
8. (Botany) botany
a. the central point of a starch granule
b. a rare name for nucellus
9. (Phonetics & Phonology) phonetics the most sonorous part of a syllable, usually consisting of a vowel or frictionless continuant
10. (Logic) logic the largest individual that is a mereological part of every member of a given class
[C18: from Latin: kernel, from nux nut]

nu•cle•us

(ˈnu kli əs, ˈnyu-)

n., pl. -cle•i (-kliˌaɪ)
-cle•us•es.
1. a central part about which other parts are grouped or gathered; core.
2. a specialized, usu. spherical mass of protoplasm encased in a double membrane and found in eukaryotic cells, directing their growth, metabolism, and reproduction, and containing most of the genetic material.
3. the positively charged mass within an atom, composed of neutrons and protons and possessing most of the mass but occupying only a small fraction of the volume of the atom.
4. a mass of nerve cells in the brain or spinal cord in which nerve fibers form connections.
5. a fundamental arrangement of atoms, as the benzene ring, that may occur in many compounds by substitution of atoms without a change in structure.
6. the condensed portion of the head of a comet.
7.
a. the central, most prominent segment in a syllable, consisting of a vowel or vowellike consonant, as the a-sound in cat or the l-sound in bottle.
b. the most prominent syllable in an utterance or stress group; tonic syllable.
[1695–1705; < Latin nuc(u)leus kernel =nuc- (s. of nux) nut + -uleus diminutive suffix]

nu·cle·us

(no͞o′klē-əs)
Plural nuclei (no͞o′klē-ī′)
1. Chemistry The positively charged central region of an atom, composed of protons and neutrons and containing most of the mass of the atom. See more at atom.
2. Biology The structure in the cytoplasm of a living cell that contains the cell's DNA and controls its metabolism, growth, and reproduction. A nucleus surrounded by a membrane is found in almost all the cells of eukaryotes and thus sets them apart from the cells of prokaryotes, such as bacteria, which do not contain nuclei. See more at cell.
3. Astronomy The solid central part of a comet, composed of ice, frozen gases, and dust.

Nucleus

 a central mass or number; a collection of persons or items to which addition will be made.
Examples: nucleus of epic cycles, 1835; of a library, 1875; of pain and pleasure, 1876; of physicists—Lipton, 1970; of fine thoughts, 1820.

nucleus

1. A cell organelle that contains the chromosomes and directs cell activities.
2. The small (about 10-14 m diameter) core of an atom. All nuclei contain positively charged protons, and all but hydrogen contain neutrons which have zero charge.
3. An atom’s positively charged core containing one or more protons and (except in hydrogen) one or more neutrons.
4. The control center in most types of cell, which contains coded genetic instructions. See chromosome, genes.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.nucleus - a part of the cell containing DNA and RNA and responsible for growth and reproductionnucleus - a part of the cell containing DNA and RNA and responsible for growth and reproduction
cell - (biology) the basic structural and functional unit of all organisms; they may exist as independent units of life (as in monads) or may form colonies or tissues as in higher plants and animals
pronucleus - the nucleus of the ovum or sperm after fertilization but before they fuse to form the nucleus of the zygote
karyoplasm, nucleoplasm - the protoplasm that constitutes the nucleus of a cell
nucleole, nucleolus - a small round body of protein in a cell nucleus; such organelles contain RNA and are involved in protein synthesis
chromatin, chromatin granule - the readily stainable substance of a cell nucleus consisting of DNA and RNA and various proteins; during mitotic division it condenses into chromosomes
achromatin - the part of a cell nucleus that is relatively uncolored by stains or dyes
linin - an obsolete term for the network of viscous material in the cell nucleus on which the chromatin granules were thought to be suspended
chromosome - a threadlike strand of DNA in the cell nucleus that carries the genes in a linear order; "humans have 22 chromosome pairs plus two sex chromosomes"
cell organ, cell organelle, organelle - a specialized part of a cell; analogous to an organ; "the first organelle to be identified was the nucleus"
subthalamic nucleus - an oval mass of grey matter located in the caudal part of the subthalamus; associated with the striate body
2.nucleus - the positively charged dense center of an atom
midpoint, centre, center - a point equidistant from the ends of a line or the extremities of a figure
nucleon - a constituent (proton or neutron) of an atomic nucleus
atom - (physics and chemistry) the smallest component of an element having the chemical properties of the element
3.nucleus - a small group of indispensable persons or things; "five periodicals make up the core of their publishing program"
set - a group of things of the same kind that belong together and are so used; "a set of books"; "a set of golf clubs"; "a set of teeth"
cadre - a nucleus of military personnel capable of expansion
4.nucleus - (astronomy) the center of the head of a comet; consists of small solid particles of ice and frozen gas that vaporizes on approaching the sun to form the coma and tail
astronomy, uranology - the branch of physics that studies celestial bodies and the universe as a whole
midpoint, centre, center - a point equidistant from the ends of a line or the extremities of a figure
comet - (astronomy) a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit
5.nucleus - any histologically identifiable mass of neural cell bodies in the brain or spinal cord
neural structure - a structure that is part of the nervous system
dentate nucleus - a large laminar nucleus of grey matter within the white matter of each cerebral hemisphere
6.nucleus - the central structure of the lens that is surrounded by the cortex
anatomical structure, bodily structure, body structure, complex body part, structure - a particular complex anatomical part of a living thing; "he has good bone structure"

nucleus

noun centre, heart, focus, basis, core, pivot, kernel, nub The Civic Movement could be the nucleus of a centrist party of the future.

nucleus

noun
A source of further growth and development:
Translations
بِذْرَهنُواة الذَّرَّه
jádro
kernenukleus
tumaydin
jezgra
atommagsejtmag
frumukjarnikjarni
原子核細胞核
atominėbranduolinė energijabranduolinisbranduolinis įtaisasbranduolinis nusiginklavimas
kodols
atom çekirdeğiçekirdekçekirdek hücrenükleon

nucleus

[ˈnjuːklɪəs] N (nuclei or nucleuses (pl)) [ˈnjuːklɪaɪ]núcleo m
the nucleus of a libraryel núcleo de una biblioteca
we have the nucleus of a crewtenemos los elementos indispensables para formar una tripulación

nucleus

[ˈnjuːkliəs] [nuclei] [ˈnjuːkliaɪ] (pl) n
[atom, cell] → noyau m
[team, side, party] → noyau m

nucleus

n pl <nuclei> (Phys, Astron, fig) → Kern m; (Biol, of cell also) → Nukleus m; atomic nucleusAtomkern m

nucleus

[ˈnjuːklɪəs] n (nuclei (pl)) [ˈnjuːklɪaɪ]nucleo

nucleus

(ˈnjuːkliəs) plural ˈnuclei (-kliai) noun
1. the central part of an atom.
2. the part of a plant or animal cell that controls its development.
nuclear (ˈnjuːkliə) adjective
1. using atomic energy. a nuclear power station; nuclear weapons.
2. of a nucleus.
ˈnuclear device noun
a device or a weapon that contains a nuclear bomb.
nuclear disarmament
the act of ceasing to store atomic weapons.
nuclear energy
atomic energy.
nuclear reactor
an apparatus for producing nuclear energy.

nu·cle·us

n. núcleo, parte esencial de una célula;
___ pulpous___ pulposo, masa gelatinosa contenida dentro de un disco intervertebral.
References in periodicals archive ?
Similarly, a 2012 report of neurotransmitter function in the oculomotor nucleus in rats states that PTSD in humans may be associated with symptoms of extraocular oblique muscle disorders, inward or vertical eye movement disorders, and ptosis [38].
The abducens has two types of neurons, motoneurons which supply the lateral rectus, and internuclear neurons, which project via the contralateral medial longitudinal fasciculus (MLF) to the contralateral oculomotor nucleus.
Its pathway involves the following primary structures: retinal cones, optic nerve, lateral geniculate nucleus, occipital lobe, posterior parietal cortex, frontal eye field (FEF), and the FEF sending projections via the internal capsule to the main oculomotor nucleus, as well as the parasympathetic accessory oculomotor nucleus (i.