Synonyms for Conglomerate (same or very similar meaning)
WordNet sense 1 (a composite rock made up of particles of varying size):
pudding stone
WordNet sense 2 (a group of diverse companies under common ownership and run as a single organization):
empire
WordNet sense 3 (made or joined or united into one):
combined
WordNet sense 4 (collect or gather):
accumulate, amass, gather, cumulate, pile up
From the ODE community, based on WordNet
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