Main Entry: belief system
Part of Speech: n
Definition: faith based on a series of beliefs but not formalized into a religion; also, a fixed coherent set of beliefs prevalent in a community or society
ev·o·lu·tion [ev-uh-loo-shuhn or, especially Brit., ee-vuh-]
–noun
Biology. change in the gene pool of a population from generation to generation by such processes as mutation, natural selection, and genetic drift.