Dr. Deferrari brings his experience as a professor of Latin and Greek at the Catholic University of America to bear in this one-of-a-kind Latin lexicon. With the assistance of Sister M. Inviolata Barry and Ignatius McGuiness, OP, Dr. Deferrari analyzes every word in St. Thomas’ Summa Theologica. The work also includes analyses of words from other works of St. Thomas where helpful in filling out St. Thomas’ Latin vocabulary.
The Logos edition of A Lexicon of Saint Thomas Aquinas integrates seamlessly with the resources already available in your Logos library. Other Latin texts in your library automatically link to this resource, allowing you to cross-reference with a click. With Logos’ powerful search functions, search results from A Lexicon of Saint Thomas Aquinas will appear alongside the results from the works already in your library.
This is an epoch-making work . . . In view of the emphasis placed by the Code of Canon Law  on the study by seminarians of St. Thomas’ philosophy and theology in their Latin texts, this monumental work has brilliant significance.
—Fr. Ignatius Smith, OP, from the Preface
Roy J. Deferrari (1890–1969) was an administrator and professor of classics at the Catholic University of America. Born in Massachusetts, Deferrari attended Princeton University, earning a PhD in 1915. Dr. Deferrari taught classics at Princeton until World War I when he served in a US Army aero squadron. After the war, Deferrari became a professor of Greek and Latin at the Catholic University of America. Dr. Deferrari was eventually appointed secretary general of the university, a position he kept until his retirement in 1960. Dr. Deferrari also published an English translation of the Collected Letters of Saint Basil.