恶化,降低,退化
Deterioration \De*te`ri*o*ra"tion\, n. [LL. deterioratio: cf. F. d['e]t['e]rioration.] The process of growing worse, or the state of having grown worse.
deterioration
n 1: a symptom of reduced quality or strength [syn: {impairment}]
2: process of changing to an inferior state [syn: {decline in
quality}, {declension}, {worsening}]