the act of differentiating.-the act of distinguishing or describing a thing, by giving its different, or specific difference; exact definition or determination.-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.-the supposed act or tendency in being of every kind, whether organic or inorganic, to assume or produce a more complex structure or functions.