Echelon
01
阶梯, 阶梯衍射光栅
a diffraction grating consisting of a pile of plates of equal thickness arranged stepwise with a constant offset
02
梯队, 梯队队形
a diagonal formation of things, especially used in military troops
03
等级, 阶层
a level or rank in an organization, profession, or society, indicating a person's status or authority within that hierarchy
例子
She worked hard for years to reach the upper echelons of the corporate world.
她努力工作多年，以达到企业世界的上层梯队。
