agglomeration (n.)

1774, "action of collecting in a mass," from Latin agglomerationem (nominative agglomeratio), noun of action from past-participle stem of agglomerare "to wind or add onto a ball," from ad "to" (see ad-) + glomerare "wind up in a ball," from glomus (genitive glomeris) "ball, ball of yarn, ball-shaped mass," which is of uncertain origin (see glebe). In reference to a mass so formed, it is recorded from 1833.