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NUCLEUS
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Irregular inflected form: nuclei
I. (noun)
Sense 1
Meaning:
The central structure of the lens that is surrounded by the cortex
Synonyms:
Classified under:
Hypernyms ("nucleus" is a kind of...):
anatomical structure; bodily structure; body structure; complex body part; structure (a particular complex anatomical part of a living thing and its construction and arrangement)
Sense 2
Meaning:
A part of the cell containing DNA and RNA and responsible for growth and reproduction
Synonyms:
cell nucleus; karyon; nucleus
Classified under:
Nouns denoting body parts
Hypernyms ("nucleus" is a kind of...):
cell organ; cell organelle; organelle (a specialized part of a cell; analogous to an organ)
Meronyms (parts of "nucleus"):
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)
Meronyms (substance of "nucleus"):
karyoplasm; nucleoplasm (the protoplasm that constitutes the nucleus of a cell)
Hyponyms (each of the following is a kind of "nucleus"):
pronucleus (the nucleus of the ovum or sperm after fertilization but before they fuse to form the nucleus of the zygote)
subthalamic nucleus (an oval mass of grey matter located in the caudal part of the subthalamus; associated with the striate body)
Holonyms ("nucleus" is a part of...):
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)
Derivation:
nucleate (form into a nucleus)
Sense 3
Meaning:
Any histologically identifiable mass of neural cell bodies in the brain or spinal cord
Classified under:
Nouns denoting body parts
Hypernyms ("nucleus" is a kind of...):
neural structure (a structure that is part of the nervous system)
Hyponyms (each of the following is a kind of "nucleus"):
dentate nucleus (a large laminar nucleus of grey matter within the white matter of each cerebral hemisphere)
Sense 4
Meaning:
A small group of indispensable persons or things
Example:
five periodicals make up the core of their publishing program
Synonyms:
core; core group; nucleus
Classified under:
Nouns denoting groupings of people or objects
Hypernyms ("nucleus" is a kind of...):
set (a group of things of the same kind that belong together and are so used)
Hyponyms (each of the following is a kind of "nucleus"):
cadre (a nucleus of military personnel capable of expansion)
Sense 5
Meaning:
The positively charged dense center of an atom
Classified under:
Nouns denoting natural objects (not man-made)
Hypernyms ("nucleus" is a kind of...):
center; centre; midpoint (a point equidistant from the ends of a line or the extremities of a figure)
Meronyms (parts of "nucleus"):
nucleon (a constituent (proton or neutron) of an atomic nucleus)
Holonyms ("nucleus" is a part of...):
atom ((physics and chemistry) the smallest component of an element having the chemical properties of the element)
Sense 6
Meaning:
(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
Classified under:
Nouns denoting natural objects (not man-made)
Hypernyms ("nucleus" is a kind of...):
center; centre; midpoint (a point equidistant from the ends of a line or the extremities of a figure)
Domain category:
astronomy; uranology (the branch of physics that studies celestial bodies and the universe as a whole)
Holonyms ("nucleus" is a part of...):
comet ((astronomy) a relatively small extraterrestrial body consisting of a frozen mass that travels around the sun in a highly elliptical orbit)
Context examples:
Morphologically, it is characterized by the presence of glycogen-rich cells with hyperchromatic nuclei.
(Ampulla of Vater Clear Cell Adenocarcinoma, NCI Thesaurus)
They carry the information from the DNA in the nucleus of the cell to the cytoplasm where the proteins are made.
(messenger RNA, NCI Dictionary)
Depending on how these galactic nuclei are oriented and what sort of material surrounds them, they appear very different when examined with telescopes.
(Black Holes Hide in Our Cosmic Backyard, NASA)
Upon activation, ERKs translocate to the nucleus and phosphorylate nuclear targets.
(Mitogen-Activated Protein Kinase, NCI Thesaurus)
The European Space Agency's (ESA) spacecraft will become the first to orbit a comet and land a probe on its nucleus.
(Rosetta closing in on comet, NASA)
The nuclei are small and round to oval in shape.
(Mouse Pancreatic Intraepithelial Neoplasia-1A, NCI Thesaurus/MMHCC)
Mitochondria depend upon genes within the nucleus for many essential messenger RNAs.
(Mitochondrion, NCI Thesaurus)
DNA wraps around histones to form chromatin, which packages DNA in the nucleus.
(Scientists find promising drug combination against lethal childhood brain cancers, National Institutes of Health)
Often form branching tubular structures, enlarged nuclei with prominent nucleolus.
(Mouse Islet Cell Adenoma, NCI Thesaurus/MMHCC)
An almond-shaped group of basal nuclei anterior to the inferior horn of the lateral ventricle of the brain, within the temporal lobe.
(Amygdala, NLM, Medical Subject Headings)
