The word 'systematic' is built upon the ancient Greek concept of sustēma, which denoted a complex whole formed by the combination or arrangement of several parts into a unified entity. This root passed into Latin as systema, retaining its core meaning of an organized, composite structure. The adjectival suffix -atic, of Greek origin via Latin, was then appended to create a term describing actions or qualities that are characteristic of, or performed according to, such a structured and methodical whole. Thus, the modern meaning evolved from the literal idea of "pertaining to a system" to the abstract sense of being methodical, orderly, and non-random, reflecting the inherent logic of a system.

Structure: system (organized whole) + atic (adjective suffix) - system: From Greek sustēma (a whole compounded of parts), via Late Latin systema. Functions as the core noun root. - atic: A suffix of Greek origin (-atikos) via Latin (-aticus), used to form adjectives meaning "of, relating to, or characterized by" the root noun.