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

Studying fuel behavior The study focused on the balance between uranium carbide and uranium oxide within the fuel kernel. —Georgina Jedikovska, Interesting Engineering, 3 Feb. 2026

The wheel could then be attached to a corn-grinding machine so that each step would help mash the kernels. —Outside, 31 Jan. 2026

The viral bit last week about essays and questionnaires was perhaps a bit overblown, but there are kernels of truth in there, too. —Jason Lloyd, New York Times, 30 Jan. 2026

Samantha Spidell attests there were some kernels of truth in his stories. —Natalie Morales, CBS News, 27 Jan. 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