The name "tertiary" comes from the Latin tertiarius meaning basically "third". Hence it has been used for centuries to denote those who belonged to a third order. Tertiaries are those persons who live according to the Third Rule of religious orders, either outside of a monastery in the world, or in a religious community. The idea which forms the basis of this institute is in general this: that persons who on account of certain circumstances cannot enter a religious order, strictly so-called, may, nevertheless, as far as possible enjoy the advantages and privileges of religious orders. This is most clearly expressed in the Rule of the Third Order of St. Francis which, although not the oldest, has, nevertheless, become the model for the rule of almost all other Third Orders. Tertiaries are divided into Regular and Secular.