permillage ———— 千分率（名词）

英文释义
(noun) Any quantity, speed, or frequency measured "per thousand".(NOTE: compare with more common "percentage"which measures per hundred)

例句

Highly sensitive scientific observations may require permillage calculations to identify tiny but significant changes in the data.

高敏感的科学观测可能需要千分率计算，以找出数据中微小但是重要的变化。