Elevation of the chalice after the consecration during a Solemn Mass
The Tridentine Mass is the Roman Rite Mass which appears in typical editions of the Roman Missal published from 1570 to 1962. The most widely used Mass liturgy in the world until the introduction of the Mass of Paul VI in 1969, it is celebrated in Liturgical Latin.
"Tridentine" is derived from the Latin Tridentinus, "related to the city of Tridentum" (modern-day Trent, Italy). In response to a decision of the Council of Trent, Italy Pope Pius V promulgated the 1570 Roman Missal, making it mandatory throughout the Western Church, except in places and religious orders with missals from before 1370. Other names used include Traditional Mass and Latin Mass, although the revised form of the Mass that replaced it has its official text in Latin and is sometimes celebrated in that language.
In 2007, Pope Benedict XVI issued the motu proprio Summorum Pontificum, accompanied by a letter to the world's bishops authorizing use of the Tridentine Mass and Ritual for competent priests. The Pope stated that the 1962 edition of the Roman Missal is to be considered an "extraordinary form" (forma extraordinaria) of the Roman Rite, of which the Missal as revised by Pope Paul VI in 1970 is the ordinary, normal or standard form. Since that is the only authorized extraordinary form, some refer to the 1962 Tridentine Mass as "the extraordinary form" of the Mass The 1962 Tridentine Mass is sometimes referred to as the "usus antiquior" (older use) or "forma antiquior" (older form), to differentiate it from the newer form of the Roman Rite in use since 1970 (also known as the Novus Ordo Mass), again in the sense of being the only one of the older forms for which authorization has been granted.
In Masses celebrated without the people, Latin Rite Catholic priests are free to use either the 1962 version of the Tridentine liturgy or the "ordinary" (normal) form of the liturgy. These Masses "may — observing all the norms of law — also be attended by faithful who, of their own free will, ask to be admitted." Permission to use the Tridentine form in parish Masses may be given by the pastor or rector.