The difference between copra and kernel
is that “copra” is the dried kernel of the coconut, from which coconut oil is extruded and “kernel” is the core, center, or essence of an object or system.
copra

kernel

Noun
 The dried kernel of the coconut, from which coconut oil is extruded.
Exemple
 She burnt a small quantity of straw and copra in an earthern incense bowl and took it out to him.

Noun
 The core, center, or essence of an object or system.
 (botany) The central (usually edible) part of a nut, especially once the hard shell has been removed.
 (botany) A single seed or grain, especially of corn or wheat.
 (botany, US) 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.
 (computing) The central part of many computer operating systems which manages the system’s resources and the communication between hardware and software components.
 (computing) The core engine of any complex software system.
 (calculus) A function used to define an integral transform.
 (mathematics) A set of pairs of a mapping’s domain which are mapped to the same value.
 (mathematics, linear algebra, functional analysis) 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}.
 (mathematics, category theory) For a category with zero morphisms: the equalizer of a given morphism and the zero morphism which is parallel to that given morphism.
 (mathematics, fuzzy set theory) The set of members of a fuzzy set that are fully included (i.e., whose grade of membership is 1).
 (chemistry) The nucleus and electrons of an atom excluding its valence electrons.
Examples
 the kernel of an argument
 Synonyms: crux, gist
 Hyponyms: microkernel, unikernel
 The Linux kernel is opensource.
 Antonym: userland
 The Dirichlet kernel convolved with a function yields its Fourier series approximation.
 If a function is continuous then its kernel is a closed set.
 Antonym: support
 Meronyms: root, zero
 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.
 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.
