1
: the inner softer part of a seed, fruit stone, or nut
… as brown in hue as hazelnuts, and sweeter than the kernels.—William Shakespeare
2
: a whole seed of a cereal
a kernel of corn
3
: a central or essential part : germ
Like many stereotypes … this one too contains some kernels of truth.—S. M. Lyman
4
chiefly dialectal
: a fruit seed
5
mathematics
: a subset of the elements of one set (such as a group) that a function (such as a homomorphism) maps onto an identity element of another set
Cite this Entry
“Kernel.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/kernel. Accessed 6 Aug. 2026.
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