nucleus

Etymology

Learned borrowing from Latin nucleus (“kernel, core”). The earliest uses refer to the head of a comet and the kernel of a seed, both recorded in Lexicon Technicum in 1704. The sense in atomic physics was coined by British scientist Michael Faraday in 1844 in a theoretical meaning.

Pronunciation

• (Received Pronunciation) IPA^(key): /ˈnjuː.kli.əs/
• (General American) IPA^(key): /ˈnuː.kli.əs/

  • Audio (US):

    (file)

Noun

nucleus (plural nuclei or nucleuses)

1. The core, central part of something, around which other elements are assembled.
   • 1968, Norton S. Ginsburg, “T’AI-PEI”, in Encyclopedia Britannica, volume 21, →LCCN, →OCLC, page 627, column 2:

     Situated in the centre of the largest agricultural basin in northern Formosa, T’ai-pei (population in 1964 was estimated to be 1,117,000) forms the nucleus of a major industrial area. The T’ai-pei industrial complex includes light and heavy industies within the urbanized area and also in several industrial suburbs, including Pan-ch’iao and Nan-chiang.

2. An initial part or version that will receive additions.

   This collection will form the nucleus of a new library.

   • 1972, Carol A. Nemeyer, Scholarly Reprint Publishing in the United States, New York, N.Y.: R. R. Bowker Co., →ISBN, page 49:

     This publishing project and the experience Power gained from wartime activities formed the nucleus for the development of the giant enterprise that today is University Microfilms, subsidiary of the Xerox Education Group, Xerox Corporation.

3. (chemistry, physics) The massive, positively charged central part of an atom, made up of protons and neutrons.

   Meronyms: proton, neutron, electron

4. (cytology) A large membrane-enclosed organelle found in eukaryotic cells which contains genetic material.
5. (neuroanatomy) A ganglion, cluster of many neuronal bodies where synapsing occurs.
6. (phonetics, phonology) The central part of a syllable, most commonly a vowel.

   Coordinate terms: onset, coda

Anagrams

• nucules, unclues

Etymology

Learned borrowing from Latin nucleus (“kernel, core”).

Pronunciation

• IPA^(key): /ˈnykleːjʏs/

• Audio:

  (file)

Noun

nucleus m (plural nucleussen or nuclei, diminutive nucleusje n)

1. nucleus, core

Alternative forms

• nuculeus

Etymology

A diminutive of nux (“nut”), with an irregular change of gender from feminine to masculine.

Pronunciation

• (Classical Latin) IPA^(key): /ˈnu.kle.us/, [ˈnʊkɫ̪eʊs̠] or IPA^(key): /ˈnuk.le.us/, [ˈnʊkɫ̪eʊs̠]
• (modern Italianate Ecclesiastical) IPA^(key): /ˈnu.kle.us/, [ˈnuːkleus] or IPA^(key): /ˈnuk.le.us/, [ˈnukleus]

Noun

nucleus m (genitive nucleī); second declension

1. (literally) (small) nut
2. kernel
3. (figuratively) core
4. nucleus

References

• “nū̆clĕus (nŭcŭlĕus)”, in Charlton T. Lewis and Charles Short (1879) A Latin Dictionary, Oxford: Clarendon Press
• nŭclĕus in Gaffiot, Félix (1934) Dictionnaire illustré latin-français, Hachette, page 1,043/1.
• “nucleus” on page 1,199 of the Oxford Latin Dictionary (1st ed., 1968–82)