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.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014
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]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
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.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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.
Dictionary of Collective Nouns and Group Terms. Copyright 2008 The Gale Group, Inc. All rights reserved.
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.
Dictionary of Unfamiliar Words by Diagram Group Copyright © 2008 by Diagram Visual Information Limited
ThesaurusAntonymsRelated WordsSynonymsLegend:
| Noun | 1. |  nucleus - a part of the cell containing DNA and RNA and responsible for growth and reproductioncell - (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" |
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
nucleus
noun centre, heart, focus, basis, core, pivot, kernel, nub The Civic Movement could be the nucleus of a centrist party of the future.
Collins Thesaurus of the English Language – Complete and Unabridged 2nd Edition. 2002 © HarperCollins Publishers 1995, 2002
nucleus
nounThe American Heritage® Roget's Thesaurus. Copyright © 2013, 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Translations
بِذْرَهنُواة الذَّرَّه
jádro
kernenukleus
tumaydin
jezgra
atommagsejtmag
frumukjarnikjarni
原子核核細胞核
atominėbranduolinė energijabranduolinisbranduolinis įtaisasbranduolinis nusiginklavimas
kodols
atom çekirdeğiçekirdekçekirdek hücrenükleon
nucleus
[ˈnjuːklɪəs] N (nuclei or nucleuses (pl)) [ˈnjuːklɪaɪ] → núcleo mthe nucleus of a library → el núcleo de una biblioteca
we have the nucleus of a crew → tenemos los elementos indispensables para formar una tripulación
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005
nucleus
[ˈnjuːkliəs] [nuclei] [ˈnjuːkliaɪ] (pl) n [atom, cell] → noyau m
[team, side, party] → noyau m
Collins English/French Electronic Resource. © HarperCollins Publishers 2005
nucleus
Collins German Dictionary – Complete and Unabridged 7th Edition 2005. © William Collins Sons & Co. Ltd. 1980 © HarperCollins Publishers 1991, 1997, 1999, 2004, 2005, 2007
Collins Italian Dictionary 1st Edition © HarperCollins Publishers 1995
nucleus
(ˈnjuːkliəs) – plural ˈnuclei (-kliai) – noun1. the central part of an atom.
2. the part of a plant or animal cell that controls its development.
nuclear (ˈnjuːkliə) adjective1. 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.
Kernerman English Multilingual Dictionary © 2006-2013 K Dictionaries Ltd.
nu·cle·us
n. núcleo, parte esencial de una célula;
___ pulpous → ___ pulposo, masa gelatinosa contenida dentro de un disco intervertebral.
English-Spanish Medical Dictionary © Farlex 2012