echelon

noun

1. a level of command, authority, or rank: After years of service, she is now in the upper echelon of city officials.
2. a level of worthiness, achievement, or reputation: studying hard to get into one of the top echelon colleges.
3. Military. a formation of troops, ships, airplanes, etc., in which groups of soldiers or individual vehicles or craft are arranged in parallel lines, either with each line extending to the right of the one in front (right echelon) or with each line extending to the left of the one in front (left echelon), so that the whole presents the appearance of steps.
4. Military. one of the groups of a formation so arranged.
5. Archaic. any structure or group of structures arranged in a steplike form.
6. Also called echelon grating. Spectroscopy. a diffraction grating that is used in the resolution of fine structure lines and consists of a series of plates of equal thickness stacked in staircase fashion.

verb (used with or without object)

7. to form in an echelon.

noun

1. a level of command, responsibility, etc (esp in the phrase the upper echelons)
2. military
   1. a formation in which units follow one another but are offset sufficiently to allow each unit a line of fire ahead
   2. a group formed in this way
3. physics a type of diffraction grating used in spectroscopy consisting of a series of plates of equal thickness arranged stepwise with a constant offset

verb

4. to assemble in echelon

n.

1796, “step-like arrangement of troops,” from French échelon “level, echelon,” literally “rung of a ladder,” from Old French eschelon, from eschiele “ladder,” from Late Latin scala “stair, slope,” from Latin scalae (plural) “ladder, steps,” from PIE *skand- “to spring, leap” (see scan). Sense of “level, subdivision” is from World War I.