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slack

nounadjectiveadverbverbnounnounnouncommon in dialogue

  • //slæk//

The part of anything that hangs loose, having no strain upon it.

noun

  1. 1

    The part of anything that hangs loose, having no strain upon it.

    the slack of a rope or of a sail

    take in the slack

  2. 2

    A dip in a surface.

    […] a road may be kept up to approximately the same level at all times, and a fair surface maintained by rolling in large patches occasionally, as well as opening slacks in the road when they appear and effecting petty repairs. […] a series of slacks will begin to show in the run of the wheels; or […]

    […] to make good the voids under the sleeper […] to take out "slacks" in the rail level […]

  3. 3

    In particular, a shallow dell or hollow; a dip in the surface of terrain, such as between hills.

    Cauldstane Slap, or rather Slack, is a much frequented pass, through which the periodical droves of black cattle are transported into England.

    ... for they had at that time observed the side of the brae, where the little green slack was situated, covered with a sheet of flame for a moment.

    Then she became a gay grey mare, / And stood in yonder slack; And he became a gilt saddle, / And sat upon her back.

    Not that every mountain stream springs from a tarn, but almost every tarn sends out a stream. Then, tarn-hunting teaches the relatively position of places almost as exactly as do the mountain-tops, leading by "backs," and "shoulders," and "slacks," and "feet," and over the lower heights straight to half a dozen seemingly irreconcilable districts[…]

  4. 4

    A low-lying marsh or a pool, especially a tidal or intermittent one which periodically fills and drains.

    The "slacks" I have mentioned are fresh-water pools which extend just inside the outer sandhills. Being mostly dry in summer, the shore fowl love to breed there. Peewits nest on their banks, and the long grasses and sand willow[…]

    ... in that quarter lay the great slack of the Watch Hill, the yellow slack that feeds the Blackburn, and in which horse and rider might readily disappear for ever.

    Modern "moonpreneurs" now hijack tidal slacks to power server farms in Nova Scotia barns, mining Bitcoin during low tides when electricity costs crater.

  5. 5

    Unconditional listening attention given by client to patient.

    The counselor is directed to give his client "free attention," or "slack," performing a kind of vigil, a version of Carl Rogers's "unconditional positive regard."

    We have apparently been doing this all our lives, since we were first distressed. This collection of ancient habits seems to be "energized" by the presence, or even the promise, of "slack" or free attention from any person in the situation […]

  6. 6

    Also a form of slacksAttributive form of slacks (“semi-formal trousers”).

    The breeches formerly worn with those spiral leggings have been succeeded by full length, slack-type trousers which are loose at the knee and around the calf.

    Recently though, slack manufacturers have been cuddling under the wings of the clothing industry to a greater extent than ever, for it has become good business to promote separate slacks and sport coats as a coordinated sales unit.

    At that time, it was customary for male college students in Peking to wear long gowns. With a pair of slacks and leather shoes, plus a scarf in the winter, Shu looked very handsome. I tried to wear the gown for two days, and gave it up because I found it difficult to reach the slack pockets under it.

Etymology

From Middle English slak, from Old English slæc (“slack”), from Proto-Germanic *slakaz. For sense of coal dust, compare slag.

adjective

  1. 1

    Lax; not tense; not firmly extended.

    a slack rope

  2. 2

    Weak; not holding fast.

    a slack hand

  3. 3

    Moderate in some capacity. Moderately warm.

    a slack oven

  4. 4

    Moderate in some capacity. Moderate in speed.

    a slack wind

  5. 5

    Lacking diligence or care; not earnest or eager.

    slack in duty or service

    The Lord is not ſlacke cõcerning his promiſe (as ſome men count ſlackneſſe)[…].

  6. 6

    Not active or busy, successful, or violent.

    Business is slack.

    the slack period following the main tourist season

    “They know our boats will stand up to their work,” said Willison, “and that counts for a good deal. A low estimate from us doesn't mean scamped work, but just for that we want to keep the yard busy over a slack time.”

    In the slack hours the service is maintained by single motor-coaches.

  7. 7

    Excess; surplus to requirements.

    the slack capacity of an oil pipeline

  8. 8

    slangVulgar; sexually explicit, especially in dancehall music.

  9. 9

    Lax.

adverb

  1. 1

    Slackly.

    slack dried hops

    Her clothes hung slack on her.

verb

  1. 1

    To slacken.

    I maruell I heare no nevves of Dromio, either hee ſlackes the matter, or betrayes his maiſter, I dare not motion anie thing to Stellio, till I knovve vvhat my boy hath don; Ile hunt him out, if the loiterſacke be gone ſpringing into a tauerne, Ile fetch him reeling out.

    In this business of growing rich, poor men […] should slack their pace.

  2. 2

    obsoleteTo mitigate; to reduce the strength of.

    Ne did ſhe let dull ſleepe once to relent, / Nor wearineſſe to ſlack her haſt, but fled / Euer alike,[…].

  3. 3

    To lose cohesion or solidity by a chemical combination with water; to slake.

    Lime slacks.

  4. 4

    To refuse to work as hard as one is supposed to.

    I can't afford to slack. This job is all I have!

Etymology

From Middle English slakken, slaken, from Old English slacian, from Proto-Germanic *slakōną (“to slack, slacken”).

noun

  1. 1

    A temporary speed restriction where track maintenance or engineering work is being carried out at a particular place.

    This pitfall, beginning in February and finishing in May, resulted in a drop of about 3 ft. in the platform level; during this period it was necessary to level the track three times weekly, and impose a service slack of 15 m.p.h. The subsidence appears now to have finished, and normal speed is once again permitted.

    The train runs slowly with frequent slacks for bridge and culvert repairs. At one point occurs the changeover from left- to right-hand running.

    A 40 m.p.h. slack at West Ruislip, quickly followed by a 30 m.p.h. slack at Gerrards Cross, increased our lateness to four minutes at High Wycombe.

Etymology

Either from the adjective in Etymology 1 or the verb in Etymology 2.

noun

  1. 1

    A valley, or small, shallow dell; a sag or saddle in a ridge.

    Red Ringan sped, and the spearmen led, Up Goranberry Slack; Aye, many a wight, unmatched in fight, Who never more came back. And bloody set the westering sun, And bloody rose he up; […]

    "I see some folk coming through the slack yonder, […]"

    […] southward, by the slack of the hill (2,500 feet), west of Ferrowie, (2,628 feet), on the County boundary, and descending by the Capel-burn to the South Esk,[…]

    Sheelings : 1. Lies South of the Infields in a Slack betwixt two Hills 2. Lies at the South End of the Loch of Loch Beanoch […]

  2. 2

    A flat-bottomed, hollow zone within a sand-dune system that has developed over impervious strata, sometimes due to erosion or blow-out of the dune system; its flat base level is therefore close to or at the permanent water-table level, and therefore has rich, marshy flora, with Salix species (willows) as typical woody colonisers.

Etymology

From Middle English slak, from Old Norse slakki (“a slope”). Cognate with Icelandic slakki, Norwegian slakke.

noun

  1. 1

    Small coal; coal dust.

    One of the important improvements of recent years has been attained by mixing the peat pulp as it passes through the grinding machine, with other inflammable materials, such as bituminous coal dust, or slack […]

    It had rather a woolly and uneven beat and was inclined to prime, but there was no trouble with steaming even though the tender contained mostly small slack and dust.

Etymology

Of unknown origin. Possibly related to Middle Dutch slacke or Middle Low German slecke. Doublet of slag.

Forms

plural
slacks
comparative
slacker
superlative
slackest
past tense
slacked
past participle
slacked
present participle
slacking
third person singular
slacks
The neighbouring pagesAlphabetical order follows the rules of the language, not byte values: an accent decides only between two otherwise identical words, and Spanish files Ñ as a letter of its own.

Lexical content from Wiktionary, under CC BY-SA 4.0 · Source entry · Data version 2026-08-23

Rank among the words of the OpenSubtitles 2018 corpus — film and television subtitles, so spoken rather than written usage (CC BY-SA 3.0).