differentiation

noun

1. The act of differentiating.
2. The act of distinguishing or describing a thing, by giving its different, or specific difference; exact definition or determination.
3. The gradual formation or production of organs or parts by a process of evolution or development, as when the seed develops the root and the stem, the initial stem develops the leaf, branches, and flower buds; or in animal life, when the germ evolves the digestive and other organs and members, or when the animals as they advance in organization acquire special organs for specific purposes.
4. (geology) The process of separation of cooling magma into various rock types.