Among the currently most popular synonyms for deteriorate are: disintegrate, undermine, go to pot, corrupt, stagnate, spoil, crumble, go to the dogs, worsen, wither, decline, slump, drop, fall, decompose, ebb, fade, fall to pieces, rot, get worse, break down, degrade, lower, decay, degenerate, regress, atrophy, slide, weaken, lessen, slip, suffer, languish, wear, collapse, retrograde, hit the skids, fall apart, depreciate, putrefy, fall down, wane, go off, sink, break up, perish, fail.