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noun \ˈjak\

Simple Definition of jack

  • : a device used for lifting something heavy (such as a car)

  • : a playing card that has a picture of a soldier or servant and that is worth more than a ten and less than a queen

  • : a small opening where something connects with a wire to something else

Full Definition of jack

  1. 1 a :  man —usually used as an intensive in such phrases as every man jack b often capitalized :  sailor c (1) :  servant, laborer (2) :  lumberjack

  2. 2 :  any of various usually mechanical devices: as a :  a device for turning a spit b :  a usually portable mechanism or device for exerting pressure or lifting a heavy body a short distance

  3. 3 :  something that supports or holds in position: as a :  an iron bar at a topgallant masthead to support a royal mast and spread the royal shrouds b :  a wooden brace fastened behind a scenic unit in a stage set to prop it up

  4. 4 a :  any of several fishes; especially :  any of various carangids b :  a male donkey c :  jackrabbit d :  any of several birds (as a jackdaw)

  5. 5 a :  a small white target ball in lawn bowling b :  a small national flag flown by a ship c (1) plural but sing in constr :  a game played with a set of small objects that are tossed, caught, and moved in various figures (2) :  a small 6-pointed metal object used in the game of jacks

  6. 6 a :  a playing card carrying the figure of a soldier or servant and ranking usually below the queen b :  jackpot 1a(2)

  7. 7 slang :  money

  8. 8 :  a female fitting in an electric circuit used with a plug to make a connection with another circuit

  9. 9 a :  applejack b :  brandy

  10. 10 :  jackknife 2

  11. 11 :  monterey jack

Examples of jack

  1. <I'd buy that watch, but I don't have the jack right now.>

  2. <a Portuguese ship flying the national jack>

Origin of jack

Middle English Jacke, familiar term of address to a social inferior, nickname for Johan John

First Known Use: 1548




Definition of jack

  1. intransitive verb
  2. :  to hunt or fish at night with a jacklight

  3. transitive verb
  4. 1 :  to hunt or fish for at night with a jacklight

  5. 2 a :  to move or lift by or as if by a jack b :  to raise the level of —usually used with up <jack up the price> c :  to take to task

jack·er noun

Circa 1841

First Known Use of jack

circa 1841

Seen and Heard

What made you want to look up jack? Please tell us where you read or heard it (including the quote, if possible).


February 13, 2016

a trying or distressing experience

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