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.

---

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

---

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

The Cornwall Space Cluster, representing Spaceport Cornwall, Goonhilly Earth Station and the National Drone Hub, a drone testing site at Predannack Airfield, is aiming to grow the data, space and aerospace industry in Cornwall.

From BBC • Apr. 18, 2026

BBC Sport visited all four venues in the Milan Cluster which will host events during the Games, which officially run between 6 and 22 February.

From BBC • Jan. 31, 2026

Ring in the New Year with the "Champagne Cluster," a distant galaxy cluster featured in a new image that combines data from NASA's Chandra X-ray Observatory and optical telescopes.

From Science Daily • Dec. 31, 2025

Additional support comes from the Deutsche Forschungsgemeinschaft through the Cluster of Excellence 'CUI: Advanced Imaging of Matter'.

From Science Daily • Nov. 21, 2025

If the Hercules Cluster is not flying apart, there must be five times more mass there, gravitationally gluing the cluster together, than we see in its galaxies.

From "Cosmos" by Carl Sagan

Related Words

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