A group of people who form an ascending chain of power or authority.
Officers in a government, for example, form an escalating series of ranks or degrees of power, with each rank subject to the authority of the one on the next level above. In a majority of hierarchical arrangements, there are a larger number of people at the bottom than at the top.
Originally, the term was used to mean government by a body of priests. Currently, a hierarchy is used to denote any body of individuals arranged or classified according to capacity, authority, position, or rank.