腐朽，腐爛；蛀蝕；衰敗；衰退。 使腐朽，使腐爛；使（牙齒）蛀壞。 腐朽，腐爛；蛀牙；衰敗；衰退。
environmental/industrial/moral/urban decay環境惡化／工業衰退／道德淪喪／城市衰落dental/tooth decay蛀牙The buildings had started to fall into decay.那些建築已經開始敗壞了。This industry has been in decay for some time.這行業早就開始息微了。
decay底開底部裂開=腐蝕
