cumulate

v. t. [ imp. & p. p. Cumulated p. pr. & vb. n. Cumulating ] [ L. cumulatus, p. p. of cumulare to heap up, fr. cumulus a heap. See Cumber. ] To gather or throw into a heap; to heap together; to accumulate. [ 1913 Webster ]

Shoals of shells, bedded and cumulated heap upon heap. Woodward. [ 1913 Webster ]