aggregationn.[Cf. LL. aggregatio, F. agrgation.] 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. (Burke.)