From Wiktionary, the free dictionary

From Middle English kernel, kirnel, kürnel, from Old English cyrnel, from Proto-West Germanic *kurnil, diminutive of Proto-Germanic *kurną (“seed, grain, corn”), equivalent to corn +‎ -le. Cognate with Yiddish קערנדל (kerndl), Middle Dutch kernel, cornel, Middle High German kornel. Related also to Old Norse kjarni (“kernel”).

• (UK) IPA^(key): /ˈkɜː.nəl/
• (US) IPA^(key): /ˈkɝ.nəl/
• (Indic, rhotic) IPA^(key): /ˈkərnəl/, (without the fern–fir–fur merger) /ˈkɛrnəl/
• (Indic, non-rhotic) IPA^(key): /ˈkɜnəl/
• Homophone: colonel (most accents)
• Rhymes: -ɜː(ɹ)nəl

kernel (plural kernels)

1. The core, center, or essence of an object or system.

   Synonyms: crux, gist; see also Thesaurus:gist

   the kernel of an argument

3. (botany) The central (usually edible) part of a nut, especially once the hard shell has been removed.
4. (botany) A single seed of grain, especially of corn or wheat.
5. (botany, US) The stone of certain fruits, such as peaches or plums.
6. A small mass around which other matter is concreted; a nucleus; a concretion or hard lump in the flesh.
7. (computing) The central part of many computer operating systems which manages the system's resources and the communication between hardware and software components.

   Antonym: userland

   Hyponyms: microkernel, unikernel

   The Linux kernel is open-source.

8. (computing) The core engine of any complex software system.
9. (programming) The simplified input to an algorithm that has undergone kernelization.
10. (calculus) A function used to define an integral transform.

    The Dirichlet kernel convolved with a function yields its Fourier series approximation.

12. (mathematics, set theory, of a function ) The set of pairs of elements in the domain of which are mapped to the same value; the equivalence relation .

13. (mathematics, algebra, loosely, of a morphism between algebraic structures) The set of elements of the domain of which are mapped to an identity element.
    1. (mathematics, group theory, of a group homomorphism between groups) The set of elements of which are mapped to the identity of (usually written as 0 in an additive group and as 1 in a multiplicative group).
    2. (mathematics, ring theory, of a ring homomorphism between rings) The set of elements of which are mapped to the additive identity 0 of .
    3. (mathematics, linear algebra, of a linear transformation between modules or vector spaces) The set of elements of which are mapped to the additive identity 0 of .

    Antonym: support

    Meronyms: root, zero

14. (mathematics, category theory, of a morphism in a category with zero morphisms) The equalizer of and the zero morphism from to , denoted .
    1. (mathematics, category theory) The source of , denoted .
15. (mathematics, fuzzy set theory) The set of members of a fuzzy set that are fully included (i.e., whose grade of membership is 1).
16. (slang) The human clitoris.

    • 2014, Karyn Gerrard, Irene Preston, Lotchie Burton, et al: Summer Heat: 10 Spicy Romances That Sizzle:

      Using the blunt end of one of the vibraphone mallets, he pried open her folds. With the balled end of the other, he rhythmically rolled over her kernel.

17. (chemistry) The nucleus and electrons of an atom excluding its valence electrons.

    • 1916, Gilbert N. Lewis, “The Atom and The Molecule”, in Journal of the American Chemical Society, 38(4) p 768:

      1. In every atom is an essential kernel which remains unaltered in all ordinary chemical changes and which possesses an excess of positive charges corresponding in number to the ordinal number of the group in the periodic table to which the element belongs.

18. This term needs a definition. Please help out and add a definition, then remove the text {{rfdef}}.

    • 2025 December 11, Charlie Campbell, Andrew R. Chow and Billy Perrigo, “The Architects of AI Are TIME’s 2025 Person of the Year”, in Time‎^[1]:

      The drumbeat of warning that advanced AI could kill us all has mostly quieted; the “doomers” have been marginalized, now used by AI’s ruling class as a punch line. Yet even the most upbeat AI leaders are quick to offer kernels of warning.

• → Japanese: カーネル (kāneru)

kernel (third-person singular simple present kernels, present participle (US) kerneling or (UK) kernelling, simple past and past participle (US) kerneled or (UK) kernelled)

1. To enclose within a kernel
2. To crenellate

• kleren

From English kernel. ^[1]

• IPA^(key): [ˈkɛrnɛl]
• Hyphenation: ker‧nel
• Rhymes: -ɛl

kernel (plural kernelek)

1. (computing) kernel (the central part of many computer operating systems)

   Synonym: rendszermag

Borrowed from English kernel, from Middle English kernel, kirnel, kürnel, from Old English cyrnel, from Proto-West Germanic *kurnil, diminutive of Proto-Germanic *kurną (“seed, grain, corn”), equivalent to corn +‎ -le.

• (Standard Indonesian) IPA^(key): /ˈkɛrnəl/ [ˈkɛr.nəl]
• Rhymes: -ɛrnəl
• Syllabification: ker‧nel

kernel (plural kernel-kernel)

1. kernel
   1. (botany, agriculture) the stone of certain fruits, such as peaches or plums. (of oil palm)
   2. (computing, information technology) the central part of many computer operating systems which manages the system's resources and the communication between hardware and software components

• “kernel”, in Kamus Besar Bahasa Indonesia [Great Dictionary of the Indonesian Language] (in Indonesian), Jakarta: Agency for Language Development and Cultivation – Ministry of Education, Culture, Research, and Technology of the Republic of Indonesia, 2016

• cernel, curnel, kernell, kirnel, karnel, kurnel, kurnele, kyrnel, kyrnell, cornel

From Old English cyrnel, from Proto-West Germanic *kurnil; equivalent to corn +‎ -el (agentive suffix). Some forms are influenced by corn.

• IPA^(key): /ˈkɛrnəl/, /ˈkirnəl/, /ˈkurnəl/, /ˈkɔrnəl/

kernel (plural kerneles)

1. The seed, grain or stone of a fruit or nut.
2. (by extension) A granule; a small grain, flake, or ball.
3. (figurative) The fundamental, superior or essential part.
4. (anatomy) An organ responsible for production of substances.
5. (medicine) A distended organ or growth.

• English: kernel
  • → Japanese: カーネル (kāneru)
• Scots: kirnel; churnel

• “kirnel, n.”, in MED Online, Ann Arbor, Mich.: University of Michigan, 2007, retrieved 6 July 2018.

• crenel

(This etymology is missing or incomplete. Please add to it, or discuss it at the Etymology scriptorium.).

kernel oblique singular, m (oblique plural kerneaus or kerneax or kerniaus or kerniax or kernels, nominative singular kerneaus or kerneax or kerniaus or kerniax or kernels, nominative plural kernel)

1. crenel (space in a battlement from which weapons may be used on an incoming enemy)

• → English: crenel
• French: créneau

• Frédéric Godefroy (1880–1902), “crenel”, in Dictionnaire de l’ancienne langue française et de tous ses dialectes du IX^e au XV^e siècle […], Paris: F[riedrich] Vieweg; Émile Bouillon, →OCLC.

Unadapted borrowing from English kernel.

kernel m (plural kernels)

1. (computing) kernel (central part of certain operating systems)
2. (calculus) kernel (a function used to define an integral transform)
3. (algebra) kernel (set of elements mapped to zero)

• núcleo