[mass noun]a failure to observe standards or show due honesty or modesty; improper behaviour or character 不适当,不正直,不谦虚;不当行为,不当性 she was scandalized at the impropriety of the question. 问题的不当让她大为愤慨。 [count noun]there are no demonstrable legal improprieties. 没有可论证的法律不当性。
语源
early 17th cent. (also in the sense 'inaccuracy, incorrectness'): from French impropriété or Latin improprietas, from improprius (see improper)