conglomerate

(noun) a composite rock made up of particles of varying size. Synonyms: pudding stone.

(noun) a group of diverse companies under common ownership and run as a single organization. Synonyms: empire.

(verb) collect or gather. Synonyms: accumulate, cumulate, pile up, gather, amass. Examples: "Journals are accumulating in my office." "The work keeps piling up."

(adj) composed of heterogeneous elements gathered into a mass. Example: "The conglomerate peoples of new england."