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

BlueMoon exploits two Chromium vulnerabilities and one in the kernel of Windows 10 (Oct 2018 Update), Windows Server 2019, Windows 10 2004, Windows Server 2022, and the initial release of Windows 11. — Dan Goodin, ArsTechnica, 9 Sep. 2026

Harvesting too early on immature beds also affects the maturation of the rice kernels over time, officials said. — Frank Vaisvilas, jsonline.com, 9 Sep. 2026

Testing fuel layer by layer TRISO, or tristructural isotropic fuel, uses a fuel kernel surrounded by multiple coating layers. — Neetika Walter, Interesting Engineering, 4 Sep. 2026

The grain is smaller than wheat, for example, and farmers and researchers are still finding the best ways to adapt farm equipment so the kernel isn't damaged during harvest. — ABC News, 4 Sep. 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