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adjective \ˈslak\

Simple Definition of slack

  • : not stretched or held in a tight position

  • : not busy : lacking the expected or desired activity

  • : doing something poorly because you are not putting enough care or effort into it

Full Definition of slack

  1. 1 :  not using due diligence, care, or dispatch :  negligent

  2. 2a :  characterized by slowness, sluggishness, or lack of energy <a slack pace>b :  moderate in some quality; especially :  moderately warm <a slack oven>c :  blowing or flowing at low speed <the tide was slack>

  3. 3a :  not tight or taut <a slack rope>b :  lacking in usual or normal firmness and steadiness :  weak <slack muscles> <slack supervision>

  4. 4 :  wanting in activity :  dull <a slack market>

  5. 5 :  lacking in completeness, finish, or perfection <a very slack piece of work>

slack·ly adverb
slack·ness noun

Examples of slack

  1. His broken arm hung slack at his side.

  2. The rope suddenly went slack.

  3. He accused the government of slack supervision of nuclear technology.

Origin of slack

Middle English slak, from Old English sleac; akin to Old High German slah slack, Latin laxus slack, loose, languēre to languish, Greek lagnos lustful and perhaps to Greek lēgein to stop

First Known Use: before 12th century

Synonym Discussion of slack

negligent, neglectful, lax, slack, remiss mean culpably careless or indicative of such carelessness. negligent implies inattention to one's duty or business <negligent about writing a note of thanks>. neglectful adds a more disapproving implication of laziness or deliberate inattention <a society callously neglectful of the poor>. lax implies a blameworthy lack of strictness, severity, or precision <a reporter lax about accurate quotation>. slack implies want of due or necessary diligence or care <slack workmanship>. remiss implies blameworthy carelessness shown in slackness, forgetfulness, or neglect <had been remiss in their familial duties>.




Simple Definition of slack

  • : to give little or no effort or attention to work

Full Definition of slack

  • intransitive verb
    1. 1 :  to be or become slack

    2. 2 :  to shirk or evade work or duty

    3. transitive verb
    4. 1a :  to be slack or negligent in performing or doingb :  lessen, moderate

    5. 2 :  to release tension on :  loosen

    6. 3a :  to cause to abateb :  slake 3

    Examples of slack

    1. They need to stop slacking and get down to work.

    2. <the skipper ordered the crew to slack off the sheets on the mainsail>

    13th Century

    First Known Use of slack

    13th century




    Definition of slack

    1. 1 :  cessation in movement or flow

    2. 2 :  a part of something that hangs loose without strain <take up the slack of a rope>

    3. 3 :  trousers especially for casual wear —usually used in plural

    4. 4 :  a dull season or period

    5. 5a :  a part that is available but not used <some slack in the budget>b :  a portion (as of labor or resources) that is required but lacking <hired a temp to take up the slack>

    6. 6 :  additional leeway or relief from pressure —usually used with cut <refused to cut me some slack on the schedule>


    First Known Use of slack





    Definition of slack

    dial English

    1. :  a pass between hills

    Origin of slack

    Middle English slak, from Old Norse slakki

    First Known Use: 14th century




    Definition of slack

    1. :  the finest screenings of coal produced at a mine unusable as fuel unless cleaned

    Origin of slack

    earlier sleck, probably from Middle Dutch slacke, slecke slag

    First Known Use: 1729

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    February 6, 2016

    an official order, decree, or edict

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