n. [ Gr. ko`smos the world + -logy: cf. F. cosmologie. ] 1. The branch of science or philosophy dealing with the origin and nature of the universe as a whole. specifically (a) (Philosophy) the branch of metaphysics speculating on the structure and nature of the most fundamental parts of the system of creation, such as space and time, the elements of bodies, the structure of the universe, the modifications of material things, causality, the laws of motion, and the order and course of nature. (b) (Astronomy) the branch of astronomy dealing with the origin and structure of the universe, including the evolution of its present observable structure, using the methods of observational astronomy as well as mathematical physics. [ 1913 Webster +PJC ]

2. a treatise dealing with the original and structure of the universe. [ 1913 Webster +PJC ]