is a specific kind of: accumulation, aggregation, assemblage, collection.

is a broader term that covers: grab bag | witch's brew, witches' brew, witches' broth | range | selection | farrago, gallimaufry, hodgepodge, hotchpotch, melange, mingle-mangle, mishmash, oddments, odds and ends, omnium-gatherum, ragbag | alphabet soup | sampler.

derivation: blend, coalesce, combine, commingle, conflate, flux, fuse, immix, meld, merge, mix | motley, variegate, vary | assorted, miscellaneous, mixed, motley, sundry.