- A small mass around which other matter is concreted; a nucleus; a concretion or hard lump in the flesh.
- (mathematics) A set of pairs of a mapping's domain which are mapped to the same value.
- (slang) The human clitoris.
- The core, center, or essence of an object or system.
"the kernel of an argument"
- (US) The stone of certain fruits, such as peaches or plums.
- (calculus) A function used to define an integral transform.
"The Dirichlet kernel convolved with a function yields its Fourier series approximation."
- (mathematics, fuzzy set theory) The set of members of a fuzzy set that are fully included (i.e., whose grade of membership is 1).
- A single seed or grain, especially of corn or wheat.
- (computing) The central part of many computer operating systems which manages the system's resources and the communication between hardware and software components.
- (mathematics, algebra) Those elements, in the domain of a function, which the function maps to zero.
"If a function is continuous then its kernel is a closed set."
- The central (usually edible) part of a nut, especially once the hard shell has been removed.