the.com/corn kernel

means One individual kernel is a single seed of corn, technically a fruit called a caryopsis, where the seed coat and fruit wall fuse into one tough little unit.

from 'Corn' traces back through Old English 'corn' to a very old root meaning simply 'worn-down particle' or 'grain' — the same root that gives us 'kernel' itself, from Old English 'cyrnel,' a diminutive of that grain-root meaning 'little seed.' So 'corn kernel' is almost a gentle redundancy, 'grain's little grain.' Confusingly, 'corn' meant any small grain in British English long before it narrowed, in America, to mean maize specifically — colonists applied the generic old word to the new crop they found here.