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