impracticality
noun [uncountable, countable](plural impracticalities)
the fact of not being sensible or realistic; a thing that is not sensible or realistic 不切实际的：不明智或不现实的事实；不明智或不现实的事情 She explained to her superiors the impracticality of such a project. 她向上级解释了这样一个项目的不可行性。