See cluster in Webster's New World Roget's A-Z Thesaurus II
noun
A number of individuals making up or considered a unit:
array, band2, batch, bevy, body, bunch, bundle, clump, clutch2, collection, group, knot, lot, party, set2. See group
verb
To come together:
assemble, collect1, congregate, convene, forgather, gather, get together, group, muster. See collectTo bring together:
assemble, call, collect1, congregate, convene, convoke, gather, get together, group, muster, round up, summon. See collect
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