#1 cluster n. [bunch, clump, clustering] a grouping of a number of similar things; "a bunch of trees"; "a cluster of admirers". wn
#2 cluster v. [constellate, flock, clump] come together as in a cluster or flock; "The poets constellate in this town every summer". wn
#3 cluster v. [bunch, bunch up, bundle, clump] gather or cause to gather into a cluster; "She bunched her fingers into a fist". wn
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