verb
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to make or become looser
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to make or become slower, less intense, etc
Other Word Forms
Etymology
Origin of slacken
Explanation
To slacken is to loosen the tension on or tightness of something. If you slacken the clothesline any more, the clothes will be on the ground next time you hang out the wash. Slacken, in the "to loosen" sense, can also be used figuratively. Because you have been so responsible, we're going to slacken the rules about curfew on non-school nights and let you stay out an hour later. Slacken also means to slow down or make less active. If you are in a sprint race, you won't want to slacken your pace until after you cross the finish line or you might not win.
Vocabulary lists containing slacken
"All Summer in a Day" by Ray Bradbury
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Excerpt from "The Adventures of Tom Sawyer"
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Flush
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Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Listeners might feel their pulse slacken as they settle into the music’s soothing triple meter, a recurring cycle of one-two-threes.
From The Wall Street Journal • Apr. 29, 2026
You absolutely must allow your lower face to slacken naturally, which may be right around the moment Kardashian parts her artificially plumped lips to make a heroic attempt at acting.
From Salon • Nov. 6, 2025
The report cautioned that it is too early to determine what caused the rate to slacken.
From BBC • Dec. 11, 2024
And, with the tight job market starting to slacken, some predict 2024 will be the year employers finally clamp down.
From Los Angeles Times • Jan. 4, 2024
Although Melynlas did not slacken speed, Taran saw the pace had begun to tell on the other horses.
From "The Black Cauldron" by Lloyd Alexander
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Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.