The character of Avraham refers to the Hebrew Bible as "the Old Testament" when talking with a group of other hasidim. An Orthodox Jew would never refer to it that way in talking to other Orthodox Jews, since it implies a "New Testament", which they categorically deny. They would instead use "Tanakh" or "Torah", but for the sake of poetic license of a television show, "Hebrew Bible" or even "Bible" would do.