slack

1 of 5

adjective

ˈslak 

1

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

2

a

: 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

a

: not tight or taut

a slack rope

b

: lacking in usual or normal firmness and steadiness : weak

slack muscles

slack supervision

4

: wanting in activity : dull

a slack market

5

: lacking in completeness, finish, or perfection

a very slack piece of work

slackly adverb

slackness noun

slack

2 of 5

verb

slacked; slacking; slacks

intransitive verb

1

: to be or become slack

2

: to shirk or evade work or duty

transitive verb

1

a

: to be slack or negligent in performing or doing

b

: lessen, moderate

2

: to release tension on : loosen

3

a

: to cause to abate

b

: slake sense 3

slack

3 of 5

noun (1)

1

: cessation in movement or flow

2

: a part of something that hangs loose without strain

take up the slack of a rope

3

: trousers especially for casual wear

—usually used in plural

4

: a dull season or period

5

a

: 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

: additional leeway or relief from pressure

—usually used with cut

refused to cut me some slack on the schedule

slack

4 of 5

noun (2)

dialectal, England

: a pass between hills

slack

5 of 5

noun (3)

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

Synonyms

Adjective

• lazy
• careless
• neglectful
• neglecting

Verb

• loosen

Noun (1)

• latitude
• space
• leeway

Choose the Right Synonym for 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

Examples of slack in a Sentence

Adjective

His broken arm hung slack at his side.

The rope suddenly went slack.

He accused the government of slack supervision of nuclear technology.

Verb

They need to stop slacking and get down to work.

the skipper ordered the crew to slack off the sheets on the mainsail

Noun (1)

our boss doesn't cut us any slack when it comes to being back from lunch on time

take up the slack of a rope

she prefers wearing slacks instead of a dress

Recent Examples on the Web

Adjective

Whenever the topic of his childhood comes up, or even something random about the war, his face goes slack and a mist seems to pass over his eyes. —Lizz Schumer, People.com, 24 June 2025

Before centre-back Gimenez could come on, more slack marking allowed Ferran Torres a free header to make it 2-2. —Dermot Corrigan, New York Times, 4 Apr. 2025

Verb

Star, hilariously, has her rope slack over her shoulder and platform teetering all over the place. —Rebecca Alter, Vulture, 1 May 2025

But when their offense has slacked, their defense has always been there to bail them out. —Kelly Iko, New York Times, 3 May 2025

Noun

Other middle-of-the-order bats — from current NL batting leader Will Smith, to June player of the month candidate Max Muncy and rising second-year star Andy Pages — have helped pick up the slack. —Jack Harris, Los Angeles Times, 27 June 2025

For the occasion, the Wolfs actor kept his look classic and wore a navy blue suit with matching slacks. —Starr Bowenbank, People.com, 26 June 2025

Word History

Etymology

Adjective

Middle English slak, slakke, going back to Old English slæc, sleac, going back to Germanic *slaka- (whence also Old Saxon slak "limp," Middle Dutch slac "loose, slack, slow," Old High German slah, Old Icelandic slakr "not tight"), o-grade of an Indo-European base *sleǵ- (or *sleh₂ǵ-) seen also in Middle Irish lac "weak, feeble," Irish lag (< *slh₂g-ko-?), Latin laxus "loosely packed, not drawn tight, relaxed" (< sl̥ǵ-so-), languere "to be enfeebled (of a person or body part)" (< *sl-n-ǵ-u̯-), Greek lagarós "loose-limbed, flexible" (< *sl̥g-ro-)

Note: Compare languish, lax entry 1, algolagnia.

Verb

derivative of slack entry 1

Noun (1)

derivative of slack entry 1

Noun (2)

Middle English slak, from Old Norse slakki

Noun (3)

earlier sleck, probably from Middle Dutch slacke, slecke slag

First Known Use

Adjective

before the 12th century, in the meaning defined at sense 1

Verb

13th century, in the meaning defined at intransitive sense 1

Noun (1)

1756, in the meaning defined at sense 1

Noun (2)

14th century, in the meaning defined above

Noun (3)

1729, in the meaning defined above

Phrases Containing slack

• give/cut (someone) some slack
• pick/take up the slack
• slack-jawed
• slack off
• slack water

Rhymes for slack

• ack
• brack
• clack
• crack
• dak
• flack
• flak
• hack
• jack
• knack
• lac
• lack

Kids Definition

slack

1 of 3 adjective

ˈslak 

1

: careless sense 2

2

: not energetic

a slack pace

3

a

: not tight : not tense or taut

a slack rope

b

: lacking in firmness : weak, soft

slack control

4

: not busy

a slack season

slackly adverb

slackness noun

slack

2 of 3 verb

1

a

: to be or become slack or careless in performing or doing

b

: lessen

the wind slacked off

2

: to avoid work or duty

3

: loosen sense 2

4

a

: to cause to lessen

b

: slake sense 4

slack

3 of 3 noun

1

: a stopping of movement or flow

2

: a part of something that hangs loose without strain

take up the slack of a rope

3

plural : trousers especially for casual wear

4

: a dull season or period : lull

5

: additional tolerance or relief from pressure

cut me some slack