of the third order, rank, stage, formation, etc.; third.
2.
Chemistry.
a.
noting or containing a carbon atom united to three other carbon atoms.
b.
formed by replacement of three atoms or groups.
3.
(initial capital letter) Geology. noting or pertaining to the period forming the earlier part of the Cenozoic Era, occurring from 65 million to 2 million years ago, characterized by the development and proliferation of mammals.
Ecclesiastical. noting or pertaining to a branch, or third order, of certain religious orders that consists of lay members living in community (regular tertiaries) or living in the world (secular tertiaries).
–noun
6.
(initial capital letter) Geology. the Tertiary Period or System.
7.
Ornithology. a tertial feather.
8.
(often initial capital letter) Ecclesiastical. a member of a tertiary branch of a religious order.
tertiary, in the Roman Catholic Church, member of a third order. The third orders are chiefly supplements of the friars—Franciscans (the most numerous), Dominicans, and Carmelites. They have rules reflecting the spirit of the corresponding order but adapted to life in the world; hence, the offices to be read are short and the fasts are mild. The promises made on joining are not vows; their purpose is the sanctification of the members. Secular members of third orders (i.e., those who live in the world) may be priests or laymen; there are also tertiaries who live in communities, the regular tertiaries. The name tertiary recalls their origin among the Franciscans, for St. Francis founded his order for laymen only after he had instituted his order for men (the friars) and after St. Clare had founded the nuns (second order, the Poor Clares). See monasticism.
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Audio Help [tur-shee-er-ee, tur-shuh-ree] Pronunciation Key adjective, noun, plural -ar·ies. 