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

After obtaining remote code execution, agents inspected the local system, identified a Linux kernel version vulnerable to a recent privilege escalation flaw, downloaded an exploit, adapted it and obtained root access. — Ron Schmelzer, Forbes.com, 7 Aug. 2026

Meanwhile, cook 2 cups yellow corn kernels in a medium skillet, preferably nonstick, over medium heat until warmed through and browned in spots, 6 to 8 minutes. — Tribune News Service, Baltimore Sun, 6 Aug. 2026

The grain is milled whole, with every part of the kernel intact, at Green Valley Farm and Mill the very same day it’s distributed to CSA (Community Supported Agriculture) members. — Laura McLively, Mercury News, 6 Aug. 2026

Eventually, the agents found a Linux kernel exploit that granted them root (or admin) privileges, leading to a rapid escalation in agent activity and attacks. — Justyn Newman, PC Magazine, 6 Aug. 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