反义词是decease，例如：
1、Conclusion The modified method could decease the error caused by residual anticoagulant.改良法可以减少血样被抗凝剂残留造成的结果误差。
2、Knowledge Economy Will Necessarily Cause Family Revolution And Its Decease.试论知识经济必将引致家庭的革命和消亡
3、Upon his decease all his properties passed to his wife.由于他的死亡，他所有的财产都过继给了他妻子。
exist反义词
反义词是
nonexistent
英 [ ˌnɒnɪɡˈzɪstənt ]
美 [ ˌnɑːnɪɡˈzɪstənt ]
不存在的常用释义
释义
adj.
不存在的
例句
1、 Pollution control measures are either not strict or nonexistent， leading to choking clouds of smog.
污染控制措施要么不严格要么不存在，导致了令人窒息的雾霾。
2、 Hygiene was nonexistent： no running water， no bathroom.
卫生根本不存在：没有自来水，没有浴室。
3、 The evidence for Mozart therapy turned out to be weak， perhaps nonexistent， although the original study never claimed anything more than a temporary and limited effect.
莫扎特疗法的证据被证明是微弱的，也许根本不存在，尽管最初的研究从来没有做过任何声明，除了说有暂时的和有限的效果。
exist反义词
反义词是inexist，中文意思是v，不存在非存在
Some people think education is a social phenomenon ， there is inexistence or not important， while the rest think education is very essential.