Tib., rin-chen gTer-mDzod chen-mo: Precious Treasure Trove of the Great Mother
Rinchen Terzö is the most often used, short form of
Rinchen Terzö Chenmo;
sometimes shortened further to Terzö (gter mdzod;
All these names refer to a 63 volume collection of revealed texts, i.e. terma, compiled and edited in the 19th century by the two Rimed masters Jamgön Kongtrül Lodrö Thaye (1813-1899) and Jamyang Khyentse Wangpo (1820-1892).
The collection consists of the most important terma hidden in the 8th and 9th centuries by Padmasambhava, Yeshe Tsogyal, Vimalamitra, and their foremost students; to be found and/or revealed in the course of history by the major terton.
The work, published in New Delhi by Dilgo Khyentse Rinpoche (1910-1991), contains many of the most important texts of the so-called Early Translation School, i.e. the Nyingma tradition; among which the 17 Tantras belonging to the Mannagde (Concealed Instruction) Series.
For a detailed discussion of the Tibetan title, its separate terms and their translations, see my article The Case of a Missing Mo.