stack

epidemic, plague, rash

bonanza, embarrassment, excess, overabundance, overage, overkill, overmuch, oversupply, plethora, redundancy, superabundance, superfluity, surfeit, surplus

deluge, flood, overflow

army, bevy, cram, crowd, crush, drove, flock, herd, horde, host, legion, mob, multitude, press, score, sea, swarm, throng

bank, bar, drift, embankment

bed, layer

mow, pyramid, rick

barrow, cairn, pyre

accumulation, aggregate, array, assemblage, collection, conglomeration, gathering, grouping, hoard, huddle, jumble, knot, pileup