kernel — English Dictionary

kernel
Pronunciations (4)
  • /ˈkɜː.nəl/
    Pronunciation notes
    • UK
  • /ˈkɝ.nəl/
    Pronunciation notes
    • US
  • ˈkɜːnəl
    Pronunciation notes
    • GB
  • ˈkɝnəl
    Pronunciation notes
    • US

Noun

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

    Synonyms
    Examples

    the kernel of an argument

  2. The central (usually edible) part of a nut, especially once the hard shell has been removed.

  3. A single seed of grain, especially of corn or wheat.

  4. The stone of certain fruits, such as peaches or plums.

    Usage
    • US usage
  5. A small mass around which other matter is concreted; a nucleus; a concretion or hard lump in the flesh.

  6. The central part of many computer operating systems which manages the system's resources and the communication between hardware and software components.

    Antonyms
    Examples

    The Linux kernel is open-source.

  7. The core engine of any complex software system.

  8. The simplified input to an algorithm that has undergone kernelization.

  9. A function used to define an integral transform.

    Examples

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

  10. The set of pairs of elements in the domain of f which are mapped to the same value; the equivalence relation x≡y⟺f(x)=f(y).

    Usage
    • of a function f
    Examples

    If a function is continuous then its kernel is a closed set.

  11. The set of elements of the domain of f which are mapped to an identity element. The set of elements of G which are mapped to the identity of H (usually written as 0 in an additive group and as 1 in a multiplicative group).

    Usage
    • broadly
    • of a group homomorphism f
    • of a morphism f between algebraic structures
    Antonyms
  12. The set of elements of the domain of f which are mapped to an identity element. The set of elements of R which are mapped to the additive identity 0 of S.

    Usage
    • broadly
    • of a ring homomorphism f
    • of a morphism f between algebraic structures
    Antonyms
  13. The set of elements of the domain of f which are mapped to an identity element. The set of elements of M which are mapped to the additive identity 0 of N.

    Usage
    • broadly
    • of a linear transformation f
    • of a morphism f between algebraic structures
    Antonyms
  14. The equalizer of f and the zero morphism from X to Y, denoted operatorname kerf.

    Usage
    • of a morphism f
  15. The equalizer of f and the zero morphism from X to Y, denoted operatorname kerf. The source of operatorname kerf, denoted operatorname Kerf.

    Usage
    • of a morphism f
  16. The set of members of a fuzzy set that are fully included (i.e., whose grade of membership is 1).

  17. The human clitoris.

    Usage
    • Slang
    Examples

    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.

  18. The nucleus and electrons of an atom excluding its valence electrons.

    Examples
    More examples (1)

    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.

Verb

  1. To enclose within a kernel

  2. To crenellate

Noun

  1. the inner and usually edible part of a seed or grain or nut or fruit stone

    Synonyms
    Examples

    black walnut kernels are difficult to get out of the shell

  2. a single whole grain of a cereal

    Broader terms
    Examples

    a kernel of corn

  3. the choicest or most essential or most vital part of some idea or experience

    Examples

    the gist of the prosecutor's argument

    the heart and soul of the Republican Party

    More examples (1)

    the nub of the story

Word forms
kernelskernelskernelingkernellingkerneledkerneledkernelledkernelled

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