Jack

/d͡ʒæk/ adj, name, noun, verb, slang

adj, name, noun, verb, slang ·Top 500 ·Elementary level

Meaning at a glance

  • Primary sense: A coarse medieval coat of defence, especially one made of leather.
  • Grammar: jack is listed as adj, name, noun, verb, slang.
  • Nearest alternatives: jackass, knave, ab, able seaman.
  • Useful contrasts: donate, drop, female donkey.
  • Usage evidence: No other boy in our class is more studious than Jack.

How to use "jack"

  1. Start with the primary definition, then check the part of speech before placing the word in a sentence.
  2. Compare nearby synonyms to make sure "jack" carries the exact meaning, tone, and strength you need.
  3. Use the example sentence as a context check. If your sentence uses the word differently, confirm that the grammar still fits.

Meaning check

  • Does the word fit the sentence's grammar?
  • Does it match the intended tone rather than only the dictionary definition?
  • Would a simpler synonym be clearer for the reader?
  • Is there enough surrounding context to prevent ambiguity?

Source and review context

This entry combines structured lexical data with WordToolSet review checks. Definitions, examples, synonyms, and usage notes may come from different source tables, so the page is designed to show evidence from more than one angle before you rely on "jack" in a final draft.

If a word has several senses, prefer the sense that matches your sentence's grammar and surrounding context. A correct definition can still be the wrong choice when the sentence needs a different register, emphasis, or level of specificity.

Before you rely on this definition

Read the first definition as a starting point, then check the example, synonyms, and part of speech before treating "jack" as the right word for your sentence.

If your draft is formal, technical, persuasive, or sensitive, compare "jack" with a nearby alternative so the final choice matches both meaning and reader expectation.

Compare nearby meanings

  • Use synonyms when you need a softer, stronger, simpler, or more specific word.
  • Use antonyms to check the boundary of the meaning and avoid accidental contrast.
  • Use the example sentence to confirm the word behaves naturally in context.
  • Keep the original wording when a replacement adds complexity without improving precision.

Definition decision workflow

1. Identify the role

Check whether "jack" is acting as adj, name, noun, verb, slang in your sentence. A definition is only useful when the grammar matches the way the word is being used.

2. Test the nearest option

Compare it with "jackass" and other nearby choices to see whether the sentence needs a softer, stronger, or more familiar word.

3. Confirm with context

Use the example sentence below as an evidence check, then read your own sentence out loud to catch tone or rhythm problems.

Review note: Definition pages are checked for source coverage, sentence evidence, synonym support, and editorial insight before they are treated as approval-ready pages. If the evidence is too thin, the page remains available to users but is kept out of the approval-facing indexed inventory.

Final meaning check

Before publishing a sentence with "jack", ask whether the word helps the reader understand the idea faster. A precise word should reduce confusion, not simply make the sentence look more polished.

When the definition, synonym evidence, and example context point in the same direction, the word is usually a safer choice. When they conflict, revise the sentence or choose a clearer alternative.

Definitions

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

    "jack of plate"

  2. 2
    A man.; A name applied to a hypothetical or typical man. capitalized

    "After Dinner they frisk away to some known Place of Rendezvous, where (at Night) every Jack has his Jill and every Jill has her Jack."

  3. 3
    The edible fruit of the Asian tree (Artocarpus heterophyllus); also the tree itself.

    "A mock living burial of the principal performer, who is placed in a pit, which is covered with planks, on the top of which a sacrifice is performed, with a fire kindled with jack wood (Artocarpus integrifolia) and a plant called erinna."

  4. 4
    A home run. slang

    "The year before ('76) Kingman had 37 jacks with only 502 PAs. Is that the limit?"

  5. 5
    A placeholder or conventional name for any man, particularly a younger, lower-class man. informal

    "Well, if you ever plan to motor west / Jack, take my way, it's the highway that's the best / Get your kicks on Route 66"

Show 56 more definitions
  1. 6
    male donkey wordnet
  2. 7
    A man.; A man, a fellow; a typical man; men in general. US, countable

    "Call you me daughter? now I promiſe you / You haue ſhewd a tender fatherly regard, / To wiſh me wed to one halfe Lunaticke, / A mad-cap ruffian, and a ſwearing Iacke, / That thinkes with oathes to face the matter out."

  3. 8
    The related tree Mangifera caesia.
  4. 9
    Ellipsis of Jack Tar, a sailor. abbreviation, alt-of, archaic, ellipsis, informal

    "When he went home on leave he rioted on a large scale—pompously. Jack ashore—with a difference—in externals only."

  5. 10
    any of several fast-swimming predacious fishes of tropical to warm temperate seas wordnet
  6. 11
    A man.; A sailor. colloquial
  7. 12
    Ellipsis of Jack Rum, a soldier. abbreviation, alt-of, archaic, ellipsis, informal
  8. 13
    tool for exerting pressure or lifting wordnet
  9. 14
    A man.; A policeman or detective; (Australia) a military policeman. slang

    "When Wardell arrived on the scene, they were surprised to find that he was unshaven, and did not look too happy. One of them remarked: "The 'Jacks' (detectives) are after you.""

  10. 15
    A jacqueminot rose.
  11. 16
    one of four face cards in a deck bearing a picture of a young prince wordnet
  12. 17
    A man.; A manual laborer. archaic
  13. 18
    small flag indicating a ship's nationality wordnet
  14. 19
    A man.; A lumberjack. Canada, US, colloquial
  15. 20
    game equipment consisting of one of several small six-pointed metal pieces that are picked up while bouncing a ball in the game of jacks wordnet
  16. 21
    A man.; A sepoy. India, historical, slang

    "I hope to God his theories will not unman him in action, that he will not be musing and refining when he should be leading the Jacks […]"

  17. 22
    an electrical device consisting of a connector socket designed for the insertion of a plug wordnet
  18. 23
    A device or utensil.; A device for turning a spit; a smokejack or roasting jack.

    "Our hero, among his other remarks, had obſerved, that in this place there was no ſuch utenſil as a jack, and that all the ſpits were turned by dogs, […]"

  19. 24
    a small ball at which players aim in lawn bowling wordnet
  20. 25
    A device or utensil.; Each of a series of blocks in a harpsichord or the earlier virginal, communicating the action of the key to the quill; sometime also, a hopper in a modern piano.

    "Do I envy those jacks that nimble leap / To kiss the tender inward of thy hand, / Whilst my poor lips, which should that harvest reap, / At the wood's boldness by thee blushing stand!"

  21. 26
    immense East Indian fruit resembling breadfruit; it contains an edible pulp and nutritious seeds that are commonly roasted wordnet
  22. 27
    A device or utensil.; a tool used in manual production of glass objects (like bottles or wine glasses).
  23. 28
    someone who works with their hands; someone engaged in manual labor wordnet
  24. 29
    A device or utensil.; A support for wood being sawn; a sawhorse or sawbuck. obsolete
  25. 30
    a man who serves as a sailor wordnet
  26. 31
    A device or utensil.; A device used to hold a boot by the heel, to assist in removing the boot.
  27. 32
    a small worthless amount wordnet
  28. 33
    A device or utensil.; A mechanical device used to raise and (temporarily) support a heavy object, now especially to lift one side of a motor vehicle when (e.g.) changing a tyre.

    "She used a jack to lift her car and changed the tire."

  29. 34
    A device or utensil.; Any of various levers for raising or lowering the sinkers which push the loops down on the needles in a knitting machine or stocking frame.
  30. 35
    A device or utensil.; A wedge for separating rocks rent by blasting. archaic
  31. 36
    A device or utensil.; A grating device used to separate and guide the threads in a warping machine; a heck-box. obsolete
  32. 37
    A device or utensil.; A machine for twisting the sliver as it leaves a carding machine, in the preparation of yarn. obsolete
  33. 38
    A device or utensil.; A switch for a jack plug, a jackknife switch; (more generally) a socket used to connect a device to a circuit, network etc.

    "telephone jack"

  34. 39
    A non-tool object or thing.; A pitcher or other vessel for holding liquid, especially alcoholic drink; a black-jack. historical, regional

    "Dead VVine that ſtinks of the Borrachio, ſup / From a fovvl Jack, or greaſie Maple Cup?"

  35. 40
    A non-tool object or thing.; The lowest court card in a deck of standard playing cards, ranking between the 10 and queen, with an image of a knave or pageboy on it.
  36. 41
    A non-tool object or thing.; A small, typically white, ball used as the target ball in bowls; a jack-ball.

    "like an uninstructed bowler, so to speak, who thinks to attain the jack, by delivering his bowl straight forward upon it"

  37. 42
    A non-tool object or thing.; A small ship's flag used as a signal or identifying device; a small flag flown at the bow of the vessel.
  38. 43
    A non-tool object or thing.; A measure of liquid corresponding to a quarter of a pint. UK, archaic, historical, regional

    "To a pound of sugar put a jack of water."

  39. 44
    A non-tool object or thing.; A fake coin designed to look like a sovereign. obsolete, slang
  40. 45
    A non-tool object or thing.; A jackcrosstree. archaic, historical
  41. 46
    A non-tool object or thing.; A small, six-pointed playing piece used in the game of jacks.
  42. 47
    A non-tool object or thing.; A torch or other light used in hunting to attract or dazzle game at night. US

    "a heron when seeing a deer attracted by the jack"

  43. 48
    A non-tool object or thing.; Money, cash. US, slang

    "First off Regan carried fifteen grand, packed it in his clothes all the time. Real money, they tell me. Not just a top card and a bunch of hay. That's a lot of jack (or jack-shit) […]."

  44. 49
    A non-tool object or thing.; A strong alcoholic liquor, especially home-distilled or illicit. Canada, US

    "[A] quart of raisin jack was divided between us with the result that tha day proper (after the night before) was spent very quietly, watered and Bromo-Seltzered, with amusing anecdotes occasionally sprouting from towelled head to towelled head."

  45. 50
    A non-tool object or thing.; Nothing, not anything, jack shit. euphemistic, slang

    "You haven't done jack. Get up and get this room cleaned up right now!"

  46. 51
    A non-tool object or thing.; The eleventh batsman to come to the crease in an innings. slang
  47. 52
    A non-tool object or thing.; A smooth often ovoid large gravel or small cobble in a natural water course. slang
  48. 53
    A plant or animal.; A pike, especially when young.
  49. 54
    A plant or animal.; A male ass, especially when kept for breeding. US
  50. 55
    A plant or animal.; Any of the marine fish in the family Carangidae.
  51. 56
    A plant or animal.; A jackrabbit. US

    "Cottontails were taken along the creeks, under the willows. Their flesh was preferable to that of the jacks[…]""

  52. 57
    A plant or animal.; A large California rockfish, the bocaccio, Sebastes paucispinis.
  53. 58
    A plant or animal.; Mangifera caesia, related to the mango tree.
  54. 59
    A plant or animal.; Plant in the genus Arisaema, also known as Jack-in-the-pulpit, and capitalized Jack. colloquial

    "Usually a jack that makes male flowers has only one main leaf (right), while female plants have two. […] The specific taxonomy of Jack-in-the Pulpit, a member of the Arum Family (Araceae), is rather up in the air. Some botanists believe all jacks are just one species, Arisaema triphyllum, while others claim there are as many as three: A. triphyllum, A. atrorubens, and A. stewardsonii."

  55. 60
    A plant or animal.; Spadix of a plant (also capitalized Jack). colloquial

    "Lifting the flap at the top of the spathe reveals our slender and round-headed friend "Jack," known better to botanists as the spadix."

  56. 61
    A plant or animal.; Plant of the genus Emex, also considered synonymous to Rumex, if not then containing two species lesser jack and little jack for Emex spinosa syn. Rumex spinosus, Australian English three-corner jack and prickly jack for Emex australis syn. Rumex hypogaeus.
Verb
  1. 1
    To physically raise using a jack. transitive

    "He jacked the car so that he could replace the brake pads."

  2. 2
    To hit (the ball) hard; especially, to hit (the ball) out of the field, producing a home run. slang, transitive

    "An excellent piece of work, Wayne thought, so good in fact, he wasn’t surprised when Bailey walked to the plate and on the first pitch jacked the ball far into the parking lot outside the left-field fence for a tournament winning homerun."

  3. 3
    hunt with a jacklight wordnet
  4. 4
    To raise or increase. transitive

    "If you want to jack your stats you just write off failures as invalid results."

  5. 5
    lift with a special device wordnet
Show 6 more definitions
  1. 6
    To increase the potency of an alcoholic beverage similarly to distillation by chilling it to below the freezing point of water, removing the water ice crystals that form, and leaving the still-liquid alcoholic portion.

    "Fruit of the orchard has been "jacked" these many generations, with Plymouth Rockers putting the hard cider barrel down into the ground to freeze, and […]"

  2. 7
    To steal (something), typically an automobile; to rob (someone). colloquial, transitive

    "Someone jacked my car last night!"

  3. 8
    To dance by moving the torso forward and backward in a rippling motion. intransitive
  4. 9
    To jack off, to masturbate. colloquial, vulgar

    "I don't even care about mine, I can get my shit off while jacking in the shower."

  5. 10
    To fight.
  6. 11
    To jerk or move by jerking; to remove or move (something). informal, intransitive, transitive
Adjective
  1. 1
    Tired, disillusioned; fed up (with). Australia

    "In the end, black and white were both crawling on the ground in reconciliation. Both saying that they were plain jack of each other."

Proper Noun
  1. 1
    A unisex given name derived from a pet form of the name John. Occasionally a diminutive of other given names such as Jackson, Jacob, Jacqueline or Jonathan. countable, uncountable

    "Since every Jack became a gentleman there's many a gentle person made a Jack."

  2. 2
    A surname. countable, uncountable
  3. 3
    Jack Daniel's, a brand of Tennessee whiskey. colloquial, countable, uncountable

    "Before I leave, brush my teeth with a bottle of Jack."

  4. 4
    An unincorporated community in Coffee County, Alabama, United States. countable, uncountable
  5. 5
    An unincorporated community in Dent County, Missouri, United States. countable, uncountable
Show 1 more definition
  1. 6
    Ellipsis of Monterey Jack, a type of cheese. abbreviation, alt-of, countable, ellipsis, uncountable

Synonyms

All synonyms
jackassknaveabable seamanable-bodied seamanace

Antonyms

donatedropfemale donkeyjenny

Example

"No other boy in our class is more studious than Jack."

Common questions

What does "jack" mean?

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

What is a synonym for "jack"?

Common synonyms include: jackass, knave, ab, able seaman, able-bodied seaman, ace.

How do you use "jack" in a sentence?

No other boy in our class is more studious than Jack.

How do you pronounce "jack"?

Pronounced /d͡ʒæk/.

Etymology

Etymology 1

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

Etymology 2

Transferred use of the personal name Jack. (cricket: eleventh batsman): An allusion to the jack in playing cards, which follows the 10.

Etymology 3

From Portuguese jaca (“jackfruit”), from Malayalam ചക്ക (cakka).

Etymology 4

From Middle English Jackin, Jankyn, a popular pet form of John; rarely also an anglicized form of French Jacques (equivalent of Jacob and James). It can be also used as nickname for Jacob. Though the name was originally a pet form, it has become more of an independent name. Equivalent to John + -kin, Jake or Jacques. See also Middle French Hennequin, Jannequin and Middle Dutch Janneken.

More for "jack"

Synonyms

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