Definition of ETHNOMEDICINE. : the comparative study of how different cultures view disease and how they treat or prevent it; also: the medical beliefs and practices of indigenous cultures.
Ten materials familiar to various prehistoric cultures are now known to be chemical elements: Carbon, copper, gold, iron, lead, mercury, silver, sulfur, tin, and zinc. Three additional materials now accepted as elements, arsenic, antimony, and bismuth, were recognized as distinct substances prior to 1500 AD.
Matter can also be classified by its chemical composition. 1  An element is a pure substance made up of atoms with the same number of protons. 2  As of 2011, 118 elements have been observed, 92 of which occur naturally. 3  Carbon (C), Oxygen (O), Hydrogen (H) are examples of elements.