The term 'power structure' refers to the hierarchical arrangement of authority and influence within a given system. The crossword solutions for this term are 'apparat' (7 letters) and 'GRID' (4 letters). Apparat is a German word meaning 'APPARATUS' or 'MACHINE, ' which can refer to a complex system of people, organizations, and institutions that work together to maintain power. GRID is a network of intersecting lines, which can be used to represent the structure of a power system, with each line representing a different level of authority.