ETYM Old Eng. kernel, kirnel, curnel, as. cyrnel, from corn grain. Related to Corn, Kern to harden.
(Homonym: colonel).
1. A single whole grain of a cereal.
2. The choicest or most essential or most vital part of some idea or experience: SYN. substance, core, center, essence, gist, heart, inwardness, marrow, meat, nub, pith, sum, nitty-gritty.
3. The inner and usually edible part of a seed or grain or nut or fruit stone; SYN. meat.
The inner, softer part of a nut, or of a seed within a hard shell.