The Collaborative International Dictionary of English v.0.48:

Congeries \Con*ge"ri*es\, n. sing. & pl. [L., fr. congerere. See
   Congest.]
   A collection of particles or bodies into one mass; a heap; an
   aggregation.
   [1913 Webster]

WordNet (r) 3.0 (2006):

congeries
    n 1: a sum total of many heterogenous things taken together
         [syn: aggregate, congeries, conglomeration]