hay·​stack | \ ˈhā-ˌstak \

Definition of haystack

1 : a stack of hay
2 : a vertical standing wave in turbulent river waters

Examples of haystack in a Sentence

Recent Examples on the Web

The haystack is smaller and has more needles in it, a change that makes the game feel more linear and also more satisfying. Andrew Cunningham, Ars Technica, "Review: Dragon Quest XI looks new but feels old," 4 Sep. 2018 Antiquing, while a nice way to spend a weekend afternoon, can be like trying to find a needle in a haystack. Jessica Cumberbatch Anderson, House Beautiful, "You Can Totally Win at Your First Country Auction. Here's How," 29 Aug. 2018 Finding the genetic differences that make one person taller or shorter than another is like looking for needles in a haystack. Brian Resnick, Vox, "How scientists are trying to predict your future with your genes," 23 Aug. 2018 Finding meteor fragments scattered on the seafloor might seem like trying to find a needle in a haystack, but the scientists participating in this hunt have a few advantages. Avery Thompson, Popular Mechanics, "Scientists Are Hunting for Meteorite Fragments Off the Coast of Washington," 3 July 2018 Finding the needle in a haystack All told, sepsis is the most costly condition treated in U.S. hospitals, affecting one in three patients who die while hospitalized. Ian Haydon, Philly.com, "Working to save lives, Philly physicians find way to help patients confront death," 26 June 2018 Toney Armstrong: That's the needle in the haystack. Josh Gelman, CBS News, "New twist in probe of slain NBA star Lorenzen Wright," 12 May 2018 Rather than stimulating the production of as many eggs as possible to find the proverbial needle in the haystack, Dr. Oxana sought to gently stimulate the production of only a handful of eggs, hoping to find one or two good ones. Elizabeth Katkin, Marie Claire, "It Took 7 Miscarriages, 10 IVF cycles, 9 Years, and Nearly $200,000 to Solve My Fertility Issues," 15 June 2018 Smartphones, web browsers and sensors provide huge quantities of information that governments can hack or collect; data centres allow them to store it indefinitely; AI helps them find needles in the digital haystacks thus assembled. The Economist, "Does China’s digital police state have echoes in the West?," 31 May 2018

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'haystack.' 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 haystack

15th century, in the meaning defined at sense 1

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Dictionary Entries near haystack





hay sweep



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Time Traveler for haystack

The first known use of haystack was in the 15th century

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More Definitions for haystack



English Language Learners Definition of haystack

: a large pile of hay


hay·​stack | \ ˈhā-ˌstak \

Kids Definition of haystack

: a large pile of hay stored outdoors

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More from Merriam-Webster on haystack

Rhyming Dictionary: Words that rhyme with haystack

Spanish Central: Translation of haystack

Nglish: Translation of haystack for Spanish Speakers

Britannica English: Translation of haystack for Arabic Speakers

Comments on haystack

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very full or close together

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