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)

clusters, present (3rd person singular) clustered, past participle, past clustering present participle

1. to gather into a cluster or clusters.

2. to furnish or cover with clusters.

verb (used without object)

clusters, present (3rd person singular) clustered, past participle, past clustering present participle

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

Derived Forms

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

Conjugated Forms

Present

• have clustered
  perfect
• has clustered
  perfect 3rd person singular
• has been clustering
  perfect progressive 3rd person singular
• are clustering
  progressive
• have been clustering
  perfect progressive
• am clustering
  progressive 1st person singular
• is clustering
  progressive 3rd person singular
• clusters
  singular 3rd person
• clustering
  participle

Past

• had clustered
  perfect
• was clustering
  progressive singular
• were clustering
  progressive plural
• had been clustering
  perfect progressive
• clustered
  simple
• clustered
  participle

Future

• will cluster
  simple
• will have clustered
  perfect
• will be clustering
  progressive
• will have been clustering
  perfect progressive

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

M88 is part of the Virgo Cluster, a vast collection of more than a thousand galaxies bound together by gravity.

From Science Daily • Jun. 1, 2026

Here, she discusses her physical and mental transformation, the importance of intimacy and the candy joy of a Nerds Gummy Cluster.

From The Wall Street Journal • May 22, 2026

The conference was organised by Iron Cluster, a group of defence groups operating out of Lviv.

From Barron's • May 15, 2026

Ilya Yablokov, who works at the University of Sheffield's Disinformation Research Cluster, encounters misinformation all the time.

From BBC • Jan. 8, 2026

A portion of the Hercules Cluster of galaxies, with about 300 known members, retreating from our region of the Cosmos at some 10,000 kilometers per second.

From "Cosmos" by Carl Sagan

Related Words

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