systematics

noun ! Definition from Wiktionary (CC BY-SA). More about systematics at Wordnik → Where our words come from →

1. The study of classification systems and nomenclature.
2. The classification system of a branch of science, especially the classification of organisms in biology.
3. A branch of Christian theology that formulates an orderly, rational, and coherent account of Christian beliefs. It comprises dogmatics, ethics and philosophy of religion.