unknowable
adj. 不可知的；不能知道的
例句
Business decisions are often made with many unknow and unknowable factors, which would even puzzle the best poker players.
商业决策通常是由许多未知和不可知的因素做出来的，这些因素甚至会让最优秀的扑克玩家感到困惑。
The specific impact of the greenhouse effect is unknowable.
温室效应的具体影响尚不可知。
《柯林斯英汉双解大词典》
The price tag for all this is unknowable.
所有这一切的价格标签是不可知的。
