[Raymond] Llull is the first author to use the expression “Immaculate Conception” to designate the Virgin’s exemption from original sin.[19] He appears to have been the first to teach this doctrine publicly at the University of Paris.
–via Wikipedia referencing Mary in the Middle Ages: the Blessed Virgin Mary in the Thought of Medieval Latin Theologians, Fr. Luigi Gambero, S.M., Ignatius Press: San Francisco, 2005.