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

Synonyms & Antonyms for slacken



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Choose the Right Synonym for slacken

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.
Recent Examples on the Web Winds slacken somewhat Friday night with colder lows in the upper 30s to low 40s. Washington Post, 23 Mar. 2022 Winds should begin to slacken overnight as the high pressure begins to weaken east of the Cascades. oregonlive, 28 Jan. 2022 Although the older variant is clinging on for dear life in a few pockets, its grasp will likely continue to slacken and slip under the weight of its craftier cousin. Katherine J. Wu, The Atlantic, 27 Jan. 2022 Heavy rain should slacken in the area by late morning as a warm front pushes the system north into British Columbia. oregonlive, 12 Jan. 2022 Norway’s power needs are usually largely met by a network of hydroelectric plants, but output can slacken when reservoirs run low. New York Times, 4 Jan. 2022 Tomorrow night: Skies are mainly clear, and winds should slacken compared to the day. Washington Post, 18 Dec. 2021 As winds also slacken, pretty much the whole area will dip to or below freezing tonight, with lows ranging from the mid-20s to low 30s. Washington Post, 19 Nov. 2021 Once the front moves through, the winds should slacken, but travel may be difficult at times with stronger gusts and heavy rain. oregonlive, 10 Dec. 2021 See More

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.

First Known Use of slacken

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

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

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Dictionary Entries Near slacken

slack coal



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Cite this Entry

“Slacken.” Dictionary, Merriam-Webster, Accessed 1 Jul. 2022.

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More Definitions for slacken


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.

More from Merriam-Webster on slacken

Nglish: Translation of slacken for Spanish Speakers

Britannica English: Translation of slacken for Arabic Speakers


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