Dar·win·ism  (där'wĭ-nĭz'əm)  n. A theory of biological evolution developed by Charles Darwin and others, stating that all species of organisms arise and develop through the natural selection of small, inherited variations that increase the individual's ability to compete, survive, and reproduce. Also called Darwinian theory. Dar'win·ist n., Dar'win·is'tic adj. |