slack·​en | \ ˈsla-kən How to pronounce slacken (audio) \
slackened; slackening\ ˈsla-​kᵊn-​iŋ How to pronounce slackening (audio) \

Definition of slacken

transitive verb

1 : to make less active : slow up slacken speed at a crossing
2 : to make slack (as by lessening tension or firmness) slacken sail

intransitive verb

1 : to become slack or slow or negligent : slow down
2 : to become less active : slack

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Synonyms & Antonyms for slacken



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delay, retard, slow, slacken, detain mean to cause to be late or behind in movement or progress. delay implies a holding back, usually by interference, from completion or arrival. bad weather delayed our arrival retard suggests reduction of speed without actual stopping. language barriers retarded their progress slow and slacken also imply a reduction of speed, slow often suggesting deliberate intention medication slowed the patient's heart rate , slacken an easing up or relaxing of power or effort. on hot days runners slacken their pace detain implies a holding back beyond a reasonable or appointed time. unexpected business had detained her

Examples of slacken in a Sentence

Sales show no sign of slackening. As he began to relax, his grip on the steering wheel slackened. The captain ordered us to slacken the sails.
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Recent Examples on the Web Democrats won control of the House in 2018 by flipping suburban districts and there was nothing in the results Tuesday night to suggest that the anti-Trump energy that powered those victories has slackened., "Analysis: Tuesday’s elections highlight the anti-Trump fervor in America’s suburbs - The Boston Globe," 7 Nov. 2019 From that moment on, the tension never slackens as Quentin initiates a city-wide manhunt for Oliver and his team, and with Oliver’s identity revealed, there feels like there’s nowhere to hide. Sydney Bucksbaum,, "We ranked every episode of Arrow," 15 Oct. 2019 Yet lower down in the troposphere, the opposite is taking place: Temperature changes are weakening the temperature gradient, and are expected to slacken the jet stream. Andrew Freedman, Anchorage Daily News, "Buckle up: Climate change is already contributing to bumpier North Atlantic flights, study finds," 7 Aug. 2019 Economists at Morgan Stanley expect the economy to grow just 1.7% this year, the slowest pace since 2012, with quarterly growth slackening to a low of 1% in the July-to-September quarter. Nick Timiraos, WSJ, "U.S. Factory Activity Decelerates Sharply Amid Global Slowdown," 3 Jan. 2019 There are also signs that business activity is slackening. Neil Irwin, New York Times, "A Recession Isn’t Inevitable: The Case for Economic Optimism," 4 Sep. 2019 While data for August are not available yet, the pace has not appeared to slacken. Los Angeles Times, "Gang crimes jump in San Diego," 3 Sep. 2019 While data for August is not available yet, the pace has not appeared to slacken. San Diego Union-Tribune, "Gang crimes spike in San Diego," 3 Sep. 2019 There is no sign of any slackening in demand for such business. The Economist, "Chinese are big customers for schemes selling foreign residency," 18 July 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'slacken.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of slacken

14th century, in the meaning defined at transitive sense 1

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Statistics for slacken

Last Updated

12 Nov 2019

Time Traveler for slacken

The first known use of slacken was in the 14th century

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More Definitions for slacken


How to pronounce slacken (audio)

English Language Learners Definition of slacken

: to become slower or less active : to slow down
: to make (something) slower or less active
: to become less tight or to make (something) less tight


slack·​en | \ ˈsla-kən How to pronounce slacken (audio) \
slackened; slackening

Kids Definition of slacken

1 : to make slower or less energetic The wind slackened.
2 : to make less tight or firm She slackened the reins.

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More from Merriam-Webster on slacken

Thesaurus: All synonyms and antonyms for slacken

Rhyming Dictionary: Words that rhyme with slacken

Spanish Central: Translation of slacken

Nglish: Translation of slacken for Spanish Speakers

Britannica English: Translation of slacken for Arabic Speakers

Comments on slacken

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to spread as a report or rumor

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