In the Roman Catholic Church, a member of a “third order” (see under holy orders); a lay person who, while marrying and following a normal employment, attempts to live in accordance with a modified version of the rule of one of the religious orders. The first such order was founded by St Francis 1221.
Period of geological time 65–1.64 million years ago, divided into five epochs: Paleocene, Eocene, Oligocene, Miocene, and Pliocene. During the Tertiary, mammals took over all the ecological niches left vacant by the extinction of the dinosaurs, and became the prevalent land animals. The continents took on their present positions, and climatic and vegetation zones as we know them became established. Within the geological time column the Tertiary follows the Cretaceous period and is succeeded by the Quaternary period.