It is often easy to determine which meaning is intended from the context. Unlike what most people think, Darwin did not claim the variations were random, nor does the theory assume the starting material was non-living matter. Because of these important details, the theory is a far cry from the modern theory of neo-darwinism. The term darwinism is often used when what is really meant is neo-darwinism. Evolution has several meanings.
Life has a history of change through time.
Living things are all related by descent from common ancestors. Darwin's theory of natural selection. Life arose by chance, therefore there is no creator. The word evolution can mean any combination of these definitions and can sometimes be determined from the context. Unfortunately, often the meaning is ambiguous.