C1 the act of believing that something is true without having any proof推定,推测,假定
The presumption of innocence is central to American law.美国法律的核心是无罪假定。
There is no scientific evidence to support such presumptions.并无科学依据支持这样的推测。
[ + that ] The decision is based on the presumption that all information must be freely available.这个决定是建立在一切信息都必须免费提供这一假定之上的。