kernel

noun

ker·​nel ˈkər-nᵊl 

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

Synonyms of kernel

• root
• core
• essence
• heart

Examples of kernel in a Sentence

There's not a kernel of truth in what they say.

the kernel of your argument seems to be the inevitability of human migration into space

Recent Examples on the Web

The company showed Kimi K3 optimizing GPU kernels, developing a GPU compiler called MiniTriton, designing a prototype AI chip using open-source electronic design automation tools, and completing a computational astrophysics workflow. — Maria Mocerino, Interesting Engineering, 19 July 2026

Planters is among several widely available brands that sell sunflower kernels at major grocery stores. — Alana Al-Hatlani, Southern Living, 16 July 2026

The patch fixes security vulnerabilities in Win32K, NTFS, Remote Desktop, Hyper-V, Secure Boot, Print Spooler, Media Foundation, the Windows installer, and the Windows kernel itself, among others. — Jon Martindale, PC Magazine, 15 July 2026

Refined grains, such as white flour, have had the bran (the outer layer of the grain kernel) and the germ (the part of the kernel that can grow into a new plant) removed during processing. — Jillian Kubala, Health, 14 July 2026

Word History

Etymology

Middle English, from Old English cyrnel, diminutive of corn

First Known Use

before the 12th century, in the meaning defined at sense 4

Phrases Containing kernel

• pine kernel

Rhymes for kernel

• colonel
• journal
• sternal
• vernal
• diurnal
• eternal
• external
• fraternal
• infernal
• internal
• maternal
• nocturnal

Kids Definition

kernel

noun

ker·​nel ˈkərn-ᵊl 

1

a

: the inner softer part of a seed, fruit stone, or nut

b

: a whole grain or seed of a cereal (as wheat or corn)

2

: a central or basic part

a kernel of truth in what they say