degeneration

n [U] (a) process of degenerating 堕落、 恶化、 退化的过程: Ageing is accompanied by a slow degeneration of his mental faculties. 他随著年纪增长, 智力逐渐衰退. (b) state of being degenerate 堕落; 恶化; 退化.

defoliation, deforest, deforestation, deform, deformation, deformed, deformity, defraud, defray, defrayal, defrock, defrost, deft, deftly, deftness, defunct, defuse, defy, deg, degenerate, degradation, degrade, degree, degrees, dehumanization, -isation, dehumanize, dehumanize, dehumanise, dehydrate, dehydration, deification, deify, deign, deism, deist, deity, deja vu, deject, dejected, dejectedly, dejection,