Aggregation

Ag·gre·ga·tion

Aggregation

n.
  1. The act of aggregating, or the state of being aggregated; collection into a mass or sum; a collection of particulars; an aggregate.
    Each genus is made up by aggregation of species.
    — Carpenter.
    A nation is not an idea only of local extent and individual momentary aggregation, but . . . of continuity, which extends in time as well as in numbers, and in space.