nucleus

Definitions

1. 1noun

   A kernel; hence, a central mass or point about which matter is gathered, or to which accretion is made; the central or material portion; -- used both literally and figuratively.

2. 2noun

   The body or the head of a comet.

3. 3noun

   An incipient ovule of soft cellular tissue.

4. 4noun

   A whole seed, as contained within the seed coats.

5. 5noun

   A body, usually spheroidal, in a cell or a protozoan, distinguished from the surrounding protoplasm by a difference in refrangibility and in behavior towards chemical reagents. It is more or less protoplasmic, and consists of a clear fluid (achromatin) through which extends a network of fibers (chromatin) in which may be suspended a second rounded body, the nucleolus (See Nucleoplasm). See Cell division, under Division.

6. 6noun

   The tip, or earliest part, of a univalve or bivalve shell.

7. 7noun

   The central part around which additional growths are added, as of an operculum.

8. 8noun

   A visceral mass, containing the stomach and other organs, in Tunicata and some mollusks.

9. 9noun

   the central structure of the lens that is surrounded by the cortex

10. 10noun

    a part of the cell containing DNA and RNA and responsible for growth and reproduction

    Synonyms

    karyon
11. 11noun

    any histologically identifiable mass of neural cell bodies in the brain or spinal cord

12. 12noun

    a small group of indispensable persons or things

    "five periodicals make up the core of their publishing program"

    Synonyms

    core
13. 13noun

    the positively charged dense center of an atom

14. 14noun

    (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