Skip to main content - Obligations, Law of
- Obrecht, Jakob
- Obrecht, M. Edmond
- Obregonians (Poor Infirmarians)
- Ocaña
- Occasion
- Occult Orders
- Occult Orders
- Oceania, The Catholic Church in
- Ochberg, Isaac
- Ochino, Bernardino
- Ochrida
- Ochs
- Ochs, Philip David
- Ochs, Siegfried
- Ockhamism
- Octobrists
- Octoechos
- Oddi, Diego, Bl.
- Odenathus and Zenobia
