jack

/d͡ʒæk/

//d͡ʒæk// noun

By · According to Wiktionary data (CC BY-SA) ·

"jack" is a 4-letter English headword indexed on PlainSpell.

The verdict

“jack” has 6 generated spelling variants in the English index at frequency #1,604. The variants make it a useful spelling check.

#1,604
frequency rank, English
796
“J” headwords
6
tracked misspellings
20
confusable pairs

According to Wiktionary data (CC BY-SA, analyzed September 3, 2026) - A coarse medieval coat of defence, especially one made of leather.

Corpus desk

Index EN-jack · jack · English

jack · rank #1,604 · 6 variants · 20 confusables

  • FREQ-COMMON #1,604
  • LEN-MID 4 letters
  • VOW-1 1 vowel
  • CONFUS-HIGH 20 pairs
  • VAR-MID 6 variants
  • BOOK-MID 796
  • PHOTO-FINISH hill

Nearest frequency peer: hill (-1 rank slots)

Read with this headword: Spelling guide for this pattern

Desk codes from Wiktionary headword shape, FrequencyWords rank tier, confusable-pair count, generated misspelling depth, letter-cohort book size, and photo-finish peer. Not a difficulty grade.

Rank peers near misspelling magnet “jack”

Same rarity band: useful when a typo lands on a peer headword

corpus weight

What this shows “jack” sits among these FrequencyWords peers; misspelling depth is tracked separately in the edit-distance chart.

Source FrequencyWords open word-frequency list As of September 3, 2026

Visual similarity to commonly confused words

How many letter changes separate each confused pair (Levenshtein distance, normalized).

jack vs JK
0% similar
jack vs Jan
25% similar
jack vs jay
50% similar

Source: PlainSpell confusable corpus (Wiktionary, CC BY-SA).

Key facts for jack
PropertyValue
Headwordjack
LanguageEnglish
Part of speechNoun
IPA/d͡ʒæk/
Letters4
Frequency rank#1,604
Misspellings tracked6
Confusable pairs20
SourceWiktionary (kaikki.org)

Frequency seat of misspelling magnet “jack”

This scale runs from the tiny cluster of words that carry ordinary speech (left) to the long tail of words almost nobody reaches for (right).jacklands here:

#1#100#1K#10K#100K
← used constantlyrarely used →

Scale is logarithmic (each tick is 10× rarer). Same rarity band neighbours include “hill” (#1,603), “larger” (#1,605), “hearing” (#1,602). Among 796 “J” headwords, “jack” is #1,604. Source: FrequencyWords open word-frequency list.

A misspelling magnet

The generator records 6 spelling variants around jack (IPA /d͡ʒæk/), anoun. Corpus frequency is #1,604 among 796 “J” headwords. Dominant gloss: "A coarse medieval coat of defence, especially one made of leather.".

Our generated misspelling index lists 6 likely wrong-spelling variants for jack, with forms such as "ajck", "jacck", and "jackk". Every one of these variants traces to a single-character edit -- an added or dropped letter, a swapped consonant, or a vowel swap -- the kind of slip a spell-checker is built to catch. It also participates in 20 confusable-pair relationships, "JK", "Jan", "jay", and more, a pairing that trips writers up because the two words share enough sound or shape to blur together.

Etymologically, the entry records: Inherited from Middle English jakke, from Anglo-Norman jacke, Middle French jaque, jacque, from jacques (“peasant”), from the proper name Jacques. Compare jacquerie. The correct English form is jack, spelled J-A-C-K.

Definition

  1. 1
    A coarse medieval coat of defence, especially one made of leather.

Recorded use

Wiktionary examples

These source excerpts show how jack appears in context. They illustrate usage; the definition above remains the entry’s reference meaning.

  1. jack of plate
  2. jack of mail

Etymology

Inherited from Middle English jakke, from Anglo-Norman jacke, Middle French jaque, jacque, from jacques (“peasant”), from the proper name Jacques. Compare jacquerie.

Common misspellings

Also misspelled as:

  • ajck
  • jacck
  • jackk
  • jakc
  • jcak
  • jjack

Misspelling Pattern Breakdown

How far each generated variant is from the correct spelling of jack - measured in single-character edits (insert, delete, or substitute a letter). Larger bars are easier to catch; one-edit slips are the sneakiest.

ajck2jacck1jackk1jakc2jcak2jjack1
Edit distance from "jack"

Definitions, pronunciation, and etymology for this entry are drawn from Wiktionary via the kaikki.org structured extract (CC BY-SA); frequency ordering uses the FrequencyWords open word-frequency list (2018 English corpus, MIT). See the methodology for how each field is sourced and updated.

Frequently Asked Questions

How do you spell "jack"?
"jack" is spelled J-A-C-K. The IPA pronunciation is /d͡ʒæk/.
What does "jack" mean?
As a noun, "jack" means: A coarse medieval coat of defence, especially one made of leather.
What words are commonly confused with "jack"?
"jack" is commonly confused with "JK", "Jan", "jay". These words look or sound similar but have different meanings. PlainSpell provides detailed comparisons for each pair.
How do you pronounce "jack"?
The IPA (International Phonetic Alphabet) transcription for "jack" is /d͡ʒæk/. Click the speaker icon on the pronunciation badge above to hear it spoken aloud where audio is available.
What is the origin of the word "jack"?
Inherited from Middle English jakke, from Anglo-Norman jacke, Middle French jaque, jacque, from jacques (“peasant”), from the proper name Jacques. Compare jacquerie. See the full etymology section above for more details.
Is PlainSpell free to use?
Yes, PlainSpell is a completely free word reference. You can look up definitions, pronunciations, confusable pairs, homophones, and spelling corrections across 5 languages without any sign-up or subscription.

Similar English words by spelling shape

Same letter count and similar misspelling depth for "jack", not the corpus desk frequency band.

Same letter count

Frequency-ranked English headwords with 4 letters (nearest by frequency rank).

hill#1,603fund#1,600pull#1,611push#1,612

Similar misspelling depth

Headwords with a similar count of attested misspellings (6 here; floor ≥5).

Louis6 variantsParis6 variantsyou'd6 variantsapply6 variants

Source: Wiktionary (via kaikki.org) Structured Wiktionary extract

Source: FrequencyWords open word-frequency list