Synonyms for Degeneration (same or very similar meaning)
WordNet sense 1 (the state of being degenerate in mental or moral qualities):
decadence, decadency, degeneracy
WordNet sense 2 (the process of declining from a higher to a lower level of effective power or vitality or essential quality):
devolution
WordNet sense 3 (passing from a more complex to a simpler biological form):
retrogression
From the ODE community, based on WordNet
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