Synonyms for Heterogeneous (same or very similar meaning)
WordNet sense 1 (including markedly dissimilar elements):
disparate
WordNet sense 2 (consisting of a haphazard assortment of different kinds (even to the point of incongruity)):
miscellaneous, mixed, motley
WordNet sense 3 (consisting of elements that are not of the same kind or nature):
heterogenous
From the ODE community, based on WordNet
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