haystack

noun

hay·​stack ˈhā-ˌstak How to pronounce haystack (audio)
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
This is because finding a world with the right atmosphere, chemistry, and geological activity is like hunting for a cosmic needle in a haystack, and this is why the search for extraterrestrial intelligence (SETI) has been such a struggle. Rupendra Brahambhatt, Interesting Engineering, 13 Sep. 2025 There’s trying to find the needle in the haystack, and then there’s building a better magnet. Expert Panel®, Forbes.com, 20 Aug. 2025 Multiple needles, multiple haystacks Technology plays a key role in helping CBP to stay one step ahead. Adam Stone, USA Today, 15 Aug. 2025 The team had to use a very fine glass needle to introduce the bacteria into mosquito eggs, a daunting task that took longer to succeed than finding a regular needle in a haystack — five years. Ari Daniel, NPR, 26 July 2025 See All Example Sentences for haystack

Word History

First Known Use

15th century, in the meaning defined at sense 1

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

Browse Nearby Words

Cite this Entry

“Haystack.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/haystack. Accessed 18 Sep. 2025.

Kids Definition

haystack

noun
hay·​stack -ˌstak How to pronounce haystack (audio)
: a stack of hay

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