clus·​ter | \ ˈklə-stər How to pronounce cluster (audio) \

Definition of cluster

 (Entry 1 of 2)

: a number of similar things that occur together: such as
a : two or more consecutive consonants or vowels in a segment of speech
b : a group of buildings and especially houses built close together on a sizable tract in order to preserve open spaces larger than the individual yard for common recreation
c : an aggregation of stars or galaxies that appear close together in the sky and are gravitationally associated the Perseus cluster of galaxies
d : a larger than expected number of cases of disease (such as leukemia) occurring in a particular locality, group of people, or period of time
e : a number of computers networked together in order to function as a single computing system Consisting of groups of inexpensive machines cobbled together, clusters in many ways have supplanted traditional supercomputers.— Elizabeth K. Wilson


clustered; clustering\ ˈklə-​st(ə-​)riŋ How to pronounce cluster (audio) \

Definition of cluster (Entry 2 of 2)

transitive verb

1 : to collect into a cluster cluster the tents together
2 : to furnish with clusters the bridge was clustered with men and officers— Herman Wouk

intransitive verb

: to grow, assemble, or occur in a cluster they clustered around the fire

Other Words from cluster


clustery \ ˈklə-​st(ə-​)rē How to pronounce cluster (audio) \ adjective

Examples of cluster in a Sentence

Noun a cluster of cottages along the shore A small cluster of people had gathered at the scene of the accident. Verb The children clustered around the storyteller. the mice clustered together into a small burrow
Recent Examples on the Web: Noun Lexus has also split the 2023 IS350 F Sport into two versions: the F Sport Design, which features mostly appearance upgrades, and the F Sport, which includes an upgraded exhaust, a different gauge cluster, and other equipment. Jack Fitzgerald, Car and Driver, 16 Sep. 2022 State health officials are investigating a cluster of Legionnaires’ disease cases, some of which are linked to a Catholic Church in southwest suburban Burbank. Rosemary Sobol, Chicago Tribune, 3 Sep. 2022 Beyond the bedroom is the house’s focal point, the great room, centered around a stainless steel sculpture resembling a cluster of giant quartz crystals — an allusion to Superman’s Fortress of Solitude. New York Times, 5 Aug. 2022 At Victor’s Lavender Farm, my nose was inches from its target, a cluster of purple buds as fragrant as a French perfumery, when a commanding voice called out from behind the planters. Andrea Sachs, Washington Post, 22 July 2022 Before being towed away in May, a cluster of disabled cars and trucks, including the green pickup (left) provided a place for people to hang out on Northeast Milton Street off 82nd Avenue. oregonlive, 17 July 2022 There are also multi-cell cluster and multi-cell line storms, both made up of a group of cells but differing in shape as indicated by the name. Anna Kaufman, USA TODAY, 16 July 2022 The other cluster, called SMACS 0723, is made up of numerous distant and faint galaxies congregating together. Michael Kan, PCMAG, 12 July 2022 Yet another familiar astronomical scene is Stephan’s Quintet, a tight cluster of galaxies, two of which are in the act of merging, about 290 million light-years from here in the constellation Pegasus. Dennis Overbye,, 10 July 2022 Recent Examples on the Web: Verb Dozens of suppliers creating thousands of additional jobs are expected to cluster around the factories, creating spillover economic benefits. Jeanne Whalen, Anchorage Daily News, 9 Sep. 2022 Massey likens this strategy to a city’s nightlife zone, where restaurants and bars tend to cluster over a few compact blocks. Outside Online, 10 Jan. 2018 At the foot of the hill, people cluster around an open casket. Murray Whyte,, 28 July 2022 In 2022, Monkeypox became a part of an ongoing viral outbreak, with most cases starting to cluster in the United Kingdom after traveling to Nigeria. Fox News, 4 Aug. 2022 On a block of L.A.'s skid row where the tents cluster corner to corner, there’s a store that most people know as the place with a little of everything. Los Angeles Times, 26 July 2022 This could explain why the hepatitis cases are so rare, linked to adenovirus infections, and appeared to cluster after pandemic restrictions were lifted, when many susceptible children became infected with common viruses, including adenoviruses. Beth Mole, Ars Technica, 25 July 2022 Roughly 45 minutes after the onset of the attack, the shooter can be heard firing four more shots as officers cluster down the hall. Chron, 12 July 2022 Artificial intelligence helps classify and cluster data, highlight key topics and trends, and flag issues quickly. Tod Nielsen, Forbes, 5 July 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cluster.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of cluster


before the 12th century, in the meaning defined above


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

History and Etymology for cluster

Noun and Verb

Middle English, from Old English clyster; akin to Old English clott clot

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Time Traveler for cluster

Time Traveler

The first known use of cluster was before the 12th century

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Dictionary Entries Near cluster



cluster analysis

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Last Updated

24 Sep 2022

Cite this Entry

“Cluster.” Dictionary, Merriam-Webster, Accessed 24 Sep. 2022.

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More Definitions for cluster


clus·​ter | \ ˈklə-stər How to pronounce cluster (audio) \

Kids Definition of cluster

 (Entry 1 of 2)

: a number of similar things growing or grouped closely together : bunch a cluster of houses a flower cluster


clustered; clustering

Kids Definition of cluster (Entry 2 of 2)

: to grow, collect, or assemble in a bunch


clus·​ter | \ ˈkləs-tər How to pronounce cluster (audio) \

Medical Definition of cluster

: a larger than expected number of cases of disease (as leukemia) occurring in a particular locality, group of people, or period of time

More from Merriam-Webster on cluster

Nglish: Translation of cluster for Spanish Speakers

Britannica English: Translation of cluster for Arabic Speakers Encyclopedia article about cluster

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