Meaning

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

  "the kernel of an argument"

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

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

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

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

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

  "The Linux kernel is open-source."

• The core engine of any complex software system.

• A function used to define an integral transform.

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

• A set of pairs of a mapping's domain which are mapped to the same value.

• For a given function (especially a linear map between vector spaces), the set of elements in the domain which are mapped to zero; (formally) given f : X → Y, the set {x ∈ X : f(x) = 0}.

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

• For a category with zero morphisms: the equalizer of a given morphism and the zero morphism which is parallel to that given morphism.

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

• The human clitoris.

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