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

These students would eventually become the kernel of domestic opposition to Yahya and his policies, culminating in his assassination in 1948. — Manfred W. Wenner, Encyclopedia Britannica, 10 Nov. 2026

The problem with rewriting the Linux kernel is half of it is driver code and nobody has that hardware anymore. — Nilay Patel, The Verge, 7 Nov. 2026

OpenAI compared the 948 vulnerabilities with historical Linux kernel bug bounty payouts from Pwn2Own and TyphoonPWN. — Neetika Walter, Interesting Engineering, 5 Nov. 2026

OpenAI says researchers used GPT-6 Cyber to find 81 previously unknown, high-severity Firefox vulnerabilities and develop working exploits for 948 Linux kernel vulnerabilities, including 588 previously unknown flaws. — Wen Shao, Fortune, 5 Nov. 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