The definition of a cluster is a group of people or things gathered or growing together.(noun)
Cluster means to grow or gather.(verb)
People grouping together is an example of to cluster.
See cluster in Webster's New World College Dictionary
Origin: ME < OE clyster, cluster; akin to north Ger dial. kluster, claw, clot
intransitive verb, transitive verb
See cluster in American Heritage Dictionary 4
Origin: Middle English
Origin: , from Old English clyster.
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