/'eʃəlɒn; `ɛʃə,lɑn/
n
1 level of authority or responsibility; rank in an organization 职权的等级; 级别
*the upper echelons of the Civil Service 政府部门的高层.
2 step-like formation of troops, aircraft, ships, etc 梯形编队
*aircraft flying in echelon, ie in a line stretching backwards to the left or right 成梯队飞行的飞机.

n[C]
[Date: 1700-1800; Language: Frenc]
alsoechelons
a rank or level of authority in an organization, business etc, or the people at that level
upper/higher/lower echelons
　the upper echelons of government
　Their clients are drawn from the highest echelons of society.
technical a line of ships, soldiers, planes etc arranged in a pattern that looks like a series of steps