piarist

from The Century Dictionary.

• noun In the Roman Catholic Church, a member of the Pauline Congregation of the Mother of God, a secular order founded at Rome by Joseph Calasanza about 1600 and sanctioned a few years later.

from the GNU version of the Collaborative International Dictionary of English.

• noun (R. C. Ch.) One of a religious order who are the regular clerks of the Scuole Pie (religious schools), an institute of secondary education, founded at Rome in the last years of the 16th century.