Standard Lemma guide

kernel

noun · verb · 23 senses · updated from the 2026-07-25 local source snapshot

Definitions and examples are grouped by meaning. Pronunciation, history, word forms, translations, descendants, synonyms, antonyms, derived terms, and related words appear whenever the source provides them.

Sound

Pronunciation

Each Play button uses your device's default local English voice, or a natural local fallback. The selected voice name appears after playback. This is synthesized speech, not a source recording.

  • UK: /ˈkɜː.nəl/
  • US: /ˈkɝ.nəl/
  • Australia: Recorded audio is listed in the source snapshot.
  • /ˈkərnəl/ South Asia, rhotic
  • /ˈkɛrnəl/ South Asia, rhotic; without the fern–fir–fur merger
  • /ˈkɜnəl/ South Asia, non-rhotic
  • homophone: colonel (most accents)
  • rhymes with -ɜː(ɹ)nəl
  • CMU ARPABET: K ER1 N AH0 L Digits mark lexical stress: 1 primary, 2 secondary, 0 unstressed.

1

noun

Meaning 1

The core, center, or essence of an object or system.

Definition source: English Wiktionary via Wiktextract

Examples

  • the kernel of an argument

Meaning relationships

Synonyms: crux, gist, bowels, sum, brass tacks, core, essence, drift, guts, gravamen, heart, heart and soul, heartstring, heartstrings, inwardness, kernel, marrow, meat, moral of the story, nitty-gritty, nub, nuts and bolts, pith, punctum saliens, quintessence, soul, spirit, stuff, substance, tenor

Antonyms: none provided

2

noun

Meaning 2

The central (usually edible) part of a nut, especially once the hard shell has been removed.

Definition source: English Wiktionary via Wiktextract

Topics: biology, botany, natural-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

3

noun

Meaning 3

A single seed of grain, especially of corn or wheat.

Definition source: English Wiktionary via Wiktextract

Topics: biology, botany, natural-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

4

noun

Meaning 4

The stone of certain fruits, such as peaches or plums.

Definition source: English Wiktionary via Wiktextract

Usage: US

Topics: biology, botany, natural-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

5

noun

Meaning 5

A small mass around which other matter is concreted; a nucleus; a concretion or hard lump in the flesh.

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

6

noun

Meaning 6

The central part of many computer operating systems which manages the system's resources and the communication between hardware and software components.

Definition source: English Wiktionary via Wiktextract

Topics: computing, engineering, mathematics, natural-sciences, physical-sciences, sciences

Examples

  • The Linux kernel is open-source.

Meaning relationships

Synonyms: none provided

Antonyms: userland

7

noun

Meaning 7

The core engine of any complex software system.

Definition source: English Wiktionary via Wiktextract

Topics: computing, engineering, mathematics, natural-sciences, physical-sciences, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

8

noun

Meaning 8

The simplified input to an algorithm that has undergone kernelization.

Definition source: English Wiktionary via Wiktextract

Topics: computing, engineering, mathematics, natural-sciences, physical-sciences, programming, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

9

noun

Meaning 9

A function used to define an integral transform.

Definition source: English Wiktionary via Wiktextract

Topics: calculus, mathematics, sciences

Examples

  • The Dirichlet kernel convolved with a function yields its Fourier series approximation.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

10

noun

Meaning 10

The set of pairs of elements in the domain of f which are mapped to the same value; the equivalence relation x≡y⟺f(x)=f(y).

Definition source: English Wiktionary via Wiktextract

Topics: mathematics, sciences, set-theory

Examples

  • If a function is continuous then its kernel is a closed set.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

11

noun

Meaning 11

The set of elements of the domain of f which are mapped to an identity element.

The set of elements of G which are mapped to the identity of H (usually written as 0 in an additive group and as 1 in a multiplicative group).

Definition source: English Wiktionary via Wiktextract

Usage: broadly

Topics: algebra, group-theory, mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: support

12

noun

Meaning 12

The set of elements of the domain of f which are mapped to an identity element.

The set of elements of R which are mapped to the additive identity 0 of S.

Definition source: English Wiktionary via Wiktextract

Usage: broadly

Qualifier: ring theory

Topics: algebra, mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: support

13

noun

Meaning 13

The set of elements of the domain of f which are mapped to an identity element.

The set of elements of M which are mapped to the additive identity 0 of N.

Definition source: English Wiktionary via Wiktextract

Usage: broadly

Topics: algebra, linear-algebra, mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: support

14

noun

Meaning 14

The equalizer of f and the zero morphism from X to Y, denoted operatorname kerf.

Definition source: English Wiktionary via Wiktextract

Topics: category-theory, computing, engineering, mathematics, natural-sciences, physical-sciences, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

15

noun

Meaning 15

The equalizer of f and the zero morphism from X to Y, denoted operatorname kerf.

The source of operatorname kerf, denoted operatorname Kerf.

Definition source: English Wiktionary via Wiktextract

Topics: category-theory, computing, engineering, mathematics, natural-sciences, physical-sciences, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

16

noun

Meaning 16

The set of members of a fuzzy set that are fully included (i.e., whose grade of membership is 1).

Definition source: English Wiktionary via Wiktextract

Qualifier: fuzzy set theory

Topics: mathematics, sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

17

noun

Meaning 17

The human clitoris.

Definition source: English Wiktionary via Wiktextract

Usage: slang

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

18

noun

Meaning 18

The nucleus and electrons of an atom excluding its valence electrons.

Definition source: English Wiktionary via Wiktextract

Topics: chemistry, natural-sciences, physical-sciences

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

19

verb

Meaning 19

To enclose within a kernel

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

20

verb

Meaning 20

To crenellate

Definition source: English Wiktionary via Wiktextract

No example sentence was provided for this meaning.

Meaning relationships

Synonyms: none provided

Antonyms: none provided

21

noun

Meaning 21

the choicest or most essential or most vital part of some idea or experience

Definition source: Princeton WordNet 3.0

Examples

  • the gist of the prosecutor's argument
  • the heart and soul of the Republican Party
  • the nub of the story

Meaning relationships

Synonyms: substance, core, center, centre, essence, gist, heart, heart and soul, inwardness, marrow, meat, nub, pith, sum, nitty-gritty

Antonyms: none provided

Broader terms: content, cognitive content, mental object

Narrower terms: bare bones, hypostasis, quiddity, haecceity, quintessence, stuff

22

noun

Meaning 22

a single whole grain of a cereal

Definition source: Princeton WordNet 3.0

Examples

  • a kernel of corn

Meaning relationships

Synonyms: none provided

Antonyms: none provided

Broader terms: grain, caryopsis

Narrower terms: corn

23

noun

Meaning 23

the inner and usually edible part of a seed or grain or nut or fruit stone

Definition source: Princeton WordNet 3.0

Examples

  • black walnut kernels are difficult to get out of the shell

Meaning relationships

Synonyms: meat

Antonyms: none provided

Broader terms: plant part, plant structure

History

Etymology

Etymology tree Proto-Indo-European *ǵerh2- Proto-Indo-European *-nóm Proto-Indo-European *ǵr̥h2-nós Proto-Indo-European *ǵr̥h2nóm Proto-Germanic *kurną Proto-West Germanic *korn Proto-Indo-European *-lósder. Proto-Germanic *-ilaz Proto-West Germanic *-il Proto-West Germanic *kurnil Old English cyrnel Middle English kirnel English kernel From Middle English kernel, kirnel, kürnel, from Old English cyrnel, from Proto-West Germanic *kurnil, diminutive of Proto-Germanic *kurną (“seed, grain, corn”), equivalent to corn + -le. Cognate with Yiddish קערנדל (kerndl), Middle Dutch kernel, cornel, Middle High German kornel. Related also to Old Norse kjarni (“kernel”).

Across languages

Translations

163 source translations are retained for this English entry.

  • Armenian: միջուկ (miǰuk) — core or essence of an object or system
  • Armenian: կորիզ (koriz) — core or essence of an object or system
  • Bulgarian: ядро́ (jadró) — core or essence of an object or system
  • Bulgarian: съ́щност (sǎ́štnost) — core or essence of an object or system
  • Chinese Mandarin: 核心 (héxīn) — core or essence of an object or system
  • Finnish: ydin — core or essence of an object or system
  • French: fond — core or essence of an object or system
  • French: cœur — core or essence of an object or system
  • Galician: cerne — core or essence of an object or system
  • Georgian: მარცვალი (marcvali) — core or essence of an object or system
  • Georgian: გული (guli) — core or essence of an object or system
  • Georgian: არსი (arsi) — core or essence of an object or system
  • German: Kern — core or essence of an object or system
  • Greek: πυρήνας (pyrínas) — core or essence of an object or system
  • Irish: eithne — core or essence of an object or system
  • Italian: nucleo — core or essence of an object or system
  • Italian: nocciolo — core or essence of an object or system
  • Japanese: 核心 (kakushin) — core or essence of an object or system
  • Korean: 핵심 (haeksim) — core or essence of an object or system
  • Macedonian: јадро (jadro) — core or essence of an object or system
  • Macedonian: срж (srž) — core or essence of an object or system
  • Māori: karihi — core or essence of an object or system
  • Middle English: kirnel — core or essence of an object or system
  • Polish: trzon — core or essence of an object or system
  • Polish: rdzeń — core or essence of an object or system
  • Polish: sedno — core or essence of an object or system
  • Portuguese: cerne — core or essence of an object or system
  • Russian: суть (sutʹ) — core or essence of an object or system
  • Russian: су́щность (súščnostʹ) — core or essence of an object or system
  • Scottish Gaelic: eitean — core or essence of an object or system
  • Scottish Gaelic: cridhe — core or essence of an object or system
  • Lower Sorbian: jědro — core or essence of an object or system
  • Spanish: núcleo — core or essence of an object or system
  • Swedish: kärna — core or essence of an object or system
  • Turkish: öz — core or essence of an object or system
  • Turkish: nüve — core or essence of an object or system
  • Yiddish: קערן (kern) — core or essence of an object or system
  • Azerbaijani: özək — central part of a nut
  • Bulgarian: я́дка (jádka) — central part of a nut
  • Czech: jádro — central part of a nut
  • Finnish: pähkinä — central part of a nut
  • French: amande — central part of a nut
  • French: cerneau — central part of a nut
  • Georgian: გული (guli) — central part of a nut
  • German: Kern — central part of a nut
  • Greek: πυρήνας (pyrínas) — central part of a nut
  • Hawaiian: ʻanoʻano — central part of a nut
  • Icelandic: kjarni — central part of a nut
  • Ingrian: toomi — central part of a nut
  • Italian: gheriglio — central part of a nut
  • Japanese: 仁 (jin) — central part of a nut
  • Macedonian: срцевина (srcevina) — central part of a nut
  • Māori: kākano — central part of a nut
  • Māori: karihi — central part of a nut
  • Māori: kiko — central part of a nut
  • Māori: kikokiko — central part of a nut
  • Middle English: kirnel — central part of a nut
  • Old English: cyrnel — central part of a nut
  • Portuguese: miolo — central part of a nut
  • Russian: ядро́ (jadró) — central part of a nut
  • Russian: сердцеви́на (serdcevína) — central part of a nut
  • Samoan: ʻaʻano — central part of a nut
  • Scottish Gaelic: eitean — central part of a nut
  • Lower Sorbian: jědro — central part of a nut
  • Spanish: almendra — central part of a nut
  • Spanish: núcleo — central part of a nut
  • Swedish: kärna — central part of a nut
  • Tongan: kano — central part of a nut
  • Turkish: göbek — central part of a nut
  • Yiddish: קערנדל (kerndl) — central part of a nut
  • Bulgarian: зърно́ (zǎrnó) — single seed of corn or wheat
  • Dutch: graan — single seed of corn or wheat
  • Finnish: jyvä — single seed of corn or wheat
  • French: grain — single seed of corn or wheat
  • Georgian: მარცვალი (marcvali) — single seed of corn or wheat
  • Gothic: 𐌺𐌰𐌿𐍂𐌽𐍉 (kaurnō) — single seed of corn or wheat
  • Ancient Greek: κόκκος (kókkos) — single seed of corn or wheat
  • Italian: chicco — single seed of corn or wheat
  • Macedonian: зрно (zrno) — single seed of corn or wheat
  • Middle English: kirnel — single seed of corn or wheat
  • Polish: ziarno — single seed of corn or wheat
  • Portuguese: grão — single seed of corn or wheat
  • Russian: зерно́ (zernó) — single seed of corn or wheat
  • Russian: зёрнышко (zjórnyško) — single seed of corn or wheat
  • Scottish Gaelic: sìol — single seed of corn or wheat
  • Spanish: grano — single seed of corn or wheat
  • Swedish: korn — single seed of corn or wheat
  • Tarifit: taɣyašt — single seed of corn or wheat
  • Turkish: tane — single seed of corn or wheat
  • Yiddish: קערנדל (kerndl) — single seed of corn or wheat
  • Armenian: կորիզ (koriz) — (US) stone of certain fruits, such as peaches or plums
  • Bashkir: һөйәк (höyək) — (US) stone of certain fruits, such as peaches or plums
  • Bulgarian: костилка (kostilka) — (US) stone of certain fruits, such as peaches or plums
  • Czech: pecka — (US) stone of certain fruits, such as peaches or plums
  • Finnish: kivi — (US) stone of certain fruits, such as peaches or plums
  • French: noyau — (US) stone of certain fruits, such as peaches or plums
  • Greek: πυρήνας (pyrínas) — (US) stone of certain fruits, such as peaches or plums
  • Greek: κουκούτσι (koukoútsi) — (US) stone of certain fruits, such as peaches or plums
  • Indonesian: kernel — (US) stone of certain fruits, such as peaches or plums
  • Italian: nocciolo — (US) stone of certain fruits, such as peaches or plums
  • Kyrgyz: өзөк (özök) — (US) stone of certain fruits, such as peaches or plums
  • Macedonian: голушка (goluška) — (US) stone of certain fruits, such as peaches or plums
  • Macedonian: коска (koska) — (US) stone of certain fruits, such as peaches or plums
  • Middle English: kirnel — (US) stone of certain fruits, such as peaches or plums
  • Polish: pestka — (US) stone of certain fruits, such as peaches or plums
  • Portuguese: caroço — (US) stone of certain fruits, such as peaches or plums
  • Russian: ко́сточка (kóstočka) — (US) stone of certain fruits, such as peaches or plums
  • Spanish: hueso — (US) stone of certain fruits, such as peaches or plums
  • Spanish: núcleo — (US) stone of certain fruits, such as peaches or plums
  • Turkish: çekirdek — (US) stone of certain fruits, such as peaches or plums
  • Turkish: nüve — (US) stone of certain fruits, such as peaches or plums
  • Abkhaz: агәаҭа (agwata) — (computing) central part of many computer operating systems
  • Arabic: نَوَاة (nawāh) — (computing) central part of many computer operating systems
  • Arabic: نواة (nuwāt) — (computing) central part of many computer operating systems
  • Bulgarian: ядро (jadro) — (computing) central part of many computer operating systems
  • Czech: jádro — (computing) central part of many computer operating systems
  • Danish: kerne — (computing) central part of many computer operating systems
  • Finnish: käyttöjärjestelmäydin — (computing) central part of many computer operating systems
  • Finnish: ydin — (computing) central part of many computer operating systems
  • Finnish: kerneli — (computing) central part of many computer operating systems
  • French: noyau — (computing) central part of many computer operating systems
  • French: kernel — (computing) central part of many computer operating systems
  • French: noyau de système d’exploitation — (computing) central part of many computer operating systems
  • German: Betriebssystemkern — (computing) central part of many computer operating systems
  • German: Kernel — (computing) central part of many computer operating systems
  • Greek: πυρήνας (pyrínas) — (computing) central part of many computer operating systems
  • Icelandic: kjarni — (computing) central part of many computer operating systems
  • Icelandic: stýrikjarni — (computing) central part of many computer operating systems
  • Indonesian: kernel — (computing) central part of many computer operating systems
  • Italian: kernel — (computing) central part of many computer operating systems
  • Japanese: カーネル (kāneru) — (computing) central part of many computer operating systems
  • Korean: 커널 (keoneol) — (computing) central part of many computer operating systems
  • Kyrgyz: өзөк (özök) — (computing) central part of many computer operating systems
  • Kyrgyz: дан (dan) — (computing) central part of many computer operating systems
  • Macedonian: јадро (jadro) — (computing) central part of many computer operating systems
  • Malay: inti — (computing) central part of many computer operating systems
  • Polish: jądro — (computing) central part of many computer operating systems
  • Polish: jajko — (computing) central part of many computer operating systems
  • Portuguese: kernel — (computing) central part of many computer operating systems
  • Portuguese: núcleo — (computing) central part of many computer operating systems
  • Russian: ядро́ (jadró) — (computing) central part of many computer operating systems
  • Spanish: núcleo — (computing) central part of many computer operating systems
  • Spanish: granelo — (computing) central part of many computer operating systems
  • Swedish: operativsystemkärna — (computing) central part of many computer operating systems
  • Swedish: kärna — (computing) central part of many computer operating systems
  • Turkish: çekirdek — (computing) central part of many computer operating systems
  • Vietnamese: nhân — (computing) central part of many computer operating systems
  • Bulgarian: ядро (jadro) — (mathematics, algebra) set of elements mapped to zero
  • Czech: jádro — (mathematics, algebra) set of elements mapped to zero
  • Danish: kerne — (mathematics, algebra) set of elements mapped to zero
  • Dutch: kern — (mathematics, algebra) set of elements mapped to zero
  • Finnish: nolla-avaruus — (mathematics, algebra) set of elements mapped to zero
  • Finnish: ydin — (mathematics, algebra) set of elements mapped to zero
  • French: noyau — (mathematics, algebra) set of elements mapped to zero
  • German: Kern — (mathematics, algebra) set of elements mapped to zero
  • Greek: πυρήνας (pyrínas) — (mathematics, algebra) set of elements mapped to zero
  • Hungarian: mag — (mathematics, algebra) set of elements mapped to zero
  • Italian: nucleo — (mathematics, algebra) set of elements mapped to zero
  • Polish: jądro — (mathematics, algebra) set of elements mapped to zero
  • Portuguese: núcleo — (mathematics, algebra) set of elements mapped to zero
  • Russian: ядро́ (jadró) — (mathematics, algebra) set of elements mapped to zero
  • Spanish: núcleo — (mathematics, algebra) set of elements mapped to zero
  • Finnish: ydin — (mathematics, fuzzy set theory) Set of members of a fuzzy set that are fully included
Real reading context

kernel in complete knowledge articles