haystack

American  

[hey-stak] / ˈheɪˌstæk /

noun

• haystacks
  plural

1. a stack of hay with a conical or ridged top, built up in the mowed field so as to prevent the accumulation of moisture and promote drying.

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haystack British  

/ ˈheɪˌrɪk, ˈheɪˌstæk /

noun

1. a large pile of hay, esp one built in the open air and covered with thatch

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haystack Idioms  

1. see needle in a haystack.

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Other Word Forms

Noun Inflected Forms

• haystacks
  plural

Etymology

Origin of haystack

1425–75; late Middle English. See hay, stack

Explanation

A haystack is a pile or bundle of hay. On farms, after hay has been cut, it's formed into haystacks until being fed to farm animals. Haystacks come in different shapes and sizes, including piles of rectangular blocks of hay; rounded bales; and pointed piles of hay. These haystacks are all packed tightly, and they're often covered to protect them from the rain. You've probably heard the phrase "a needle in a haystack," an idiom that's used when a search is on for some impossibly tiny thing that's lost.

Example Sentences

See Examples For:

haystack haystacks

"This isn't like detecting a needle in a haystack. It's like detecting a microscopic portion of a needle in a haystack," said Steven Manderach, executive director of the Association of Food and Drug Officials.

From BBC ● Jul. 14, 2026

The best place to hide needles is in a haystack.

From MarketWatch ● Jun. 10, 2026

The process can take months for a single archaeological site and often feels like searching for a needle in a haystack.

From Science Daily ● May 11, 2026

Maven was built to find the needle in the haystack.

From Barron's ● Apr. 5, 2026

We were this close to that haystack, and our doom.

From "Secrets at Sea" by Richard Peck

I’ve used AI to summarize vast swaths of documents and pull needles from giant haystacks.

From The Wall Street Journal ● Oct. 9, 2025

"It's not just one needle in a haystack, but one needle in several haystacks," Singapore's second minister for home affairs, Josephine Teo, told parliament in October last year.

From BBC ● Apr. 12, 2024

"You really are fishing needles out of haystacks."

From Science Daily ● Mar. 20, 2024

They gave speeches in front of haystacks and wandered around in dad jeans pressing the flesh.

From Salon ● Jun. 5, 2023

She was lost in thought about needles and haystacks, and all she heard was the quiet click of the library door closing behind her.

From "The Interrupted Tale" by Maryrose Wood