Deuterocanonical Literally “of the second canon.” A term used in modern biblical studies to designate the books that are not part of the Hebrew Bible but are considered part of the canonical Old Testament for certain Christian traditions and are included in early Christian Bibles in Greek and Latin.

The term “deuterocanonical” is Catholic in origin and primarily refers to books included in the Roman Catholic Old Testament canon that are not included in the Hebrew Bible (Tobit, Judith, Wisdom of Solomon, Sirach, Baruch (including the Letter of Jeremiah), and 1 and 2 Maccabees, as well as the Additions to Daniel and Additions to Esther). This remains its sense in Catholic writings. Secondarily, however, the term may be used to refer to books in the Old Testament canon of any Christian group that are not included in the Hebrew Bible, such as 3 Maccabees for the Eastern Orthodox tradition and Jubilees for the Ethiopian Orthodox tradition. Since the books in question are not part of the Hebrew Bible, they are usually referred to as “apocrypha” or “apocryphal” by Protestants.

The term “deuterocanonical” was first used in 1566 by the Catholic theologian Sixtus of Siena. His definition was slightly different: He used it to refer to books included in the Catholic canon of the Bible that took longer to become recognized as canonical than others; he contrasted them with the “protocanonical” books that were quickly recognized. In addition to the books listed above as deuterocanonical for Catholics, his list of deuterocanonical books included the Old Testament book of Esther and the New Testament books of Hebrews, James, 2 Peter, 2 and 3 John, Jude, and Revelation (Hayes, “Historical Criticism,” 991).

The term “deuterocanonical” is preferred in biblical studies over the terms “apocrypha” and “apocryphal” because the terms “apocrypha” and “apocryphal” may impose modern value judgments that do not align with the viewpoints of early Christianity and Judaism on the works in question. However, as used in modern biblical studies, the term “deuterocanonical” does carry an implication that the books so designated were composed later than the books of the Hebrew Bible.

The deuterocanonical books are sometimes also referred to as “intertestamental literature”; however, that is a broad term that also includes the Old Testament Pseudepigrapha and other books written between the end of the Hebrew Bible and the beginning of the New Testament.