Roman Catechism 7.6

Chapter 7 — Part I: The Creed — Article V: He Descended into Hell; the Third Day He Rose Again from the Dead

Section 6. Different Abodes Called Hell" — These abodes are not all of the same nature, for among them is that most loathsome and dark prison in which the souls of the damned are tormented with the unclean spirits in eternal and inextinguishable fire. This place is called gehenna, the bottomless pit, and is hell strictly so-called.