cluster

American  

[kluhs-ter] / ˈklʌs tər /

noun

1. a number of things of the same kind, growing or held together; a bunch.

   a cluster of grapes.

2. a group of things or persons close together.

   There was a cluster of tourists at the gate.

3. U.S. Army. a small metal design placed on a ribbon representing an awarded medal to indicate that the same medal has been awarded again.

   oak-leaf cluster.

4. Phonetics. a succession of two or more contiguous consonants in an utterance, as the str- cluster of strap.

5. Astronomy. a group of neighboring stars, held together by mutual gravitation, that have essentially the same age and composition and thus supposedly a common origin.

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verb (used with object)

1. to gather into a cluster or clusters.

2. to furnish or cover with clusters.

verb (used without object)

1. to form a cluster or clusters.

   The people clustered around to watch.

   Synonyms:

   bunch, crowd, throng, gather, group

cluster British  

/ ˈklʌstə /

noun

1. a number of things growing, fastened, or occurring close together

2. a number of persons or things grouped together

3. military a metal insignia worn on a medal ribbon to indicate a second award or a higher class of a decoration or order

4. military

   1. a group of bombs dropped in one stick, esp fragmentation and incendiary bombs

   2. the basic unit of mines used in laying a minefield

5. astronomy an aggregation of stars or galaxies moving together through space

6. a group of two or more consecutive vowels or consonants

7. statistics a naturally occurring subgroup of a population used in stratified sampling

8. chem

   1. a chemical compound or molecule containing groups of metal atoms joined by metal-to-metal bonds

   2. the group of linked metal atoms present

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verb

1. to gather or be gathered in clusters

Other Word Forms

• clustered
  adjective
• clusteringly
  adverb
• clustery
  adjective
• intercluster
  adjective
• subcluster
  noun
• unclustered
  adjective
• unclustering
  adjective

Etymology

Origin of cluster

before 900; Middle English; Old English cluster, clyster bunch; cognate with Low German kluster

Explanation

A cluster is a small group of people or things. When you and your friends huddle awkwardly around the snack table at a party, whispering and trying to muster enough nerve to hit the dance floor, you’ve formed a cluster. Cluster comes to us from the Old English word clyster, meaning bunch. Nowadays, you can use cluster as either a noun or a verb. When we were kids, we would stand in a cluster (noun) on the street corner, eagerly awaiting the appearance of the Good Humor truck every afternoon. Then we would cluster (verb) eagerly around the driver, demanding ice cream. Virtually anything can form a cluster — flowers, cells, stars, human beings, and even events.

Example Sentences

It is the cluster: foundries, packaging houses, substrate suppliers, materials firms, equipment engineers, testing specialists, design-service providers and process experts operating in close proximity.

From The Wall Street Journal • May 13, 2026

Each cluster also had a mass exceeding 170,000 atomic mass units, making them heavier than most proteins.

From Science Daily • May 11, 2026

In the current cluster, the type of hantavirus involved is called the Andes virus, found in South America.

From Barron's • May 7, 2026

In January, she reached out to Sidonio, her former colleague who first recognized the 2013 cluster of cases there, for advice.

From Salon • May 7, 2026

An explosion goes off, perilously close to a cluster of dry-looking leaves and branches.

From "I Can Make This Promise" by Christine Day

Related Words

• array
• assemblage
• band
• batch
• bunch
• bundle
• chunk
• clump
• collection
• knot