: 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
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
: to grow, assemble, or occur in a cluster
they clustered around the fire
Cite this Entry
“Cluster.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cluster. Accessed 27 Oct. 2026.
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