Catholic Encyclopedia · Alphabetical Index
A
Catholic Encyclopedia Entries Beginning with A
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A
Catholic Encyclopedia Entries
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AA
3 entriesAB
83 entries- Abachum, Audifax, Martha, and Maris, Saints
- Abaddon
- Abandonment
- Abarca, Pedro
- Abarim
- Abba
- Abbadie, Antoine d’
- Abban of Magheranoidhe, Saint
- Abban of New Ross, Saint
- Abban the Hermit, Saint
- Abbé
- Abbeloos, Jean Baptiste
- Abbess
- Abbey
- Abbo Cernuus
- Abbon, Saint
- Abbot
- Abbot, Commendatory
- Abbot, Henry
- Abbot, Lay
- Abbreviation, Methods of
- Abbreviations, Ecclesiastical
- Abbreviators
- Abdera
- Abdias
- Abdias of Babylon
- Abdication
- Abdon and Sennen, Saints
- Abduction
- Abecedaria
- Abecedarians
- Abel
- Abel
- Abel, Blessed Thomas
- Abelard, Peter
- Abelly, Louis
- Aben-Ezra, Abraham-ben-Méir
- Abenakis
- Abercius, Inscription of
- Abercromby, John
- Abercromby, Robert
- Aberdeen, The Diocese of
- Aberdeen, The University of
- Aberle, Moritz von
- Abgar, The Legend of
- Abhan, Saint
- Abiathar
- Abila
- Abingdon, The Abbey of
- Abington, Thomas
- Abiogenesis and Biogenesis
- Abipones
- Abisai
- Abjuration
- Abner
- Abomination of Desolation, The
- Abortion
- Abortion, Physical Effects of
- Abra de Raconis, Charles François d’
- Abrabanel, Don Isaac
- Abraham
- Abraham a Sancta Clara
- Abraham Ecchelensis
- Abraham (in Liturgy)
- Abraham, The Bosom of
- Abrahamites
- Abram, Nicholas
- Abrasax
- Absalom
- Absalon of Lund
- Absinthe
- Absolute, The
- Absolution
- Abstemii
- Abstinence
- Abstinence, Physical Effects of
- Abstraction
- Abthain
- Abucara, Theodore
- Abundius
- Abydus
- Abyss
- Abyssinia
AC
80 entries- Acacia
- Acacians, The
- Acacius
- Acacius
- Acacius
- Acacius, Saint
- Academies, Roman
- Academy, The French
- Acadia
- Acanthus
- Acanthus
- Acathistus
- Acca, Saint
- Accaron
- Accentus Ecclesiasticus
- Acceptance
- Acceptants
- Accession
- Accessus
- Acciajuoli
- Accident
- Acclamation
- Acclamation (in Papal Elections)
- Accommodation, Biblical
- Accomplice
- Accursius, Francesco
- Acephali
- Acerenza
- Achab
- Achaia
- Achaicus
- Achaz
- Achéry, Lucas d’
- Achiacharus
- Achilleus and Nereus, Domitilla and Pancratius, Saints
- Achimaas
- Achimelech
- Achitopel
- Achonry
- Achor Valley
- Achrida
- Achterfeldt, Johann Heinrich
- Achtermann, Theodore William
- Aci-Reale, The Diocese of
- Acidalius, Valens
- Ackermann, Leopold
- Acmonia
- Acoemetae
- Acolouthia
- Acolyte
- Acosta, Joaquín
- Acosta, José de
- Acquapendente
- Acquaviva
- Acquaviva
- Acquaviva, Claudius
- Acqui
- Acre
- Acre
- Acrostic
- Act of Settlement (Irish)
- Acta Pilati
- Acta Sanctæ Sedis
- Acta Sanctorum Hiberniæ
- Acta Triadis Thaumaturgæ
- Acton, Charles Januarius
- Acton, John
- Acton, John Emerich Edward Dalberg, Baron Acton
- Acton, John Francis Edward
- Acts, Canonical
- Acts, Human
- Acts, Indifferent
- Acts of Roman Congregations
- Acts of the Apostles
- Acts of the Martyrs
- Actual Grace
- Actus et Potentia
- Actus primus
- Actus Purus
- Acuas
AD
88 entries- Ad Apostolicae Dignitatis Apicem
- Ad Limina Apostolorum
- Ad Limina Visit
- Ad Sanctam Beati Petri Sedem
- Ad Universalis Ecclesiae
- Adalard, Saint
- Adalbert
- Adalbert I
- Adalbert, Saint
- Adalbert, Saint
- Adam
- Adam in Early Christian Liturgy and Literature
- Adam, John
- Adam, Nicholas
- Adam of Bremen
- Adam of Fulda
- Adam of Murimuth
- Adam of Perseigne
- Adam of St. Victor
- Adam of Usk
- Adam Scotus
- Adam, The Books of
- Adami da Bolsena, Andrea
- Adamites
- Adamnan, Saint
- Adams, James
- Adams, Ven. John
- Adana
- Adar
- Adauctus and Felix, Saints
- Adda, Ferdinando d’
- Addai, Doctrine of
- Addas
- Addeus and Maris, Liturgy of
- Addresses, Ecclesiastical
- Adelaide, Archdiocese of
- Adelaide, Saint
- Adelaide, Saint
- Adelard of Bath
- Adelham, John Placid
- Adelmann
- Adelophagi
- Aden
- Adeodatus
- Adeodatus I, Pope Saint
- Adeodatus (II), Pope Saint
- Adeste Fidelis
- Adjuration
- Administrator
- Administrator (of Ecclesiastical Property)
- Admonitions, Canonical
- Admont
- Ado of Vienne, Saint
- Adonai
- Adonias
- Adoption
- Adoption, Canonical
- Adoption, Supernatural
- Adoptionism
- Adoration
- Adoration, Perpetual
- Adorno, Francis
- Adoro Te Devote
- Adria
- Adrian I, Pope
- Adrian II, Pope
- Adrian III, Pope Saint
- Adrian IV, Pope
- Adrian of Canterbury, Saint
- Adrian of Castello
- Adrian V, Pope
- Adrian VI, Pope
- Adrianople
- Adrichem, Christian Kruik van
- Adso
- Aduarte, Diego Francisco
- Adullam
- Adulteration of Food
- Adultery
- Advent
- Adventists
- Advertisements, Book of
- Advocates of Roman Congregations
- Advocates of St. Peter
- Advocatus Diaboli
- Advocatus Ecclesiæ
- Advowson
- Adytum
AE
14 entriesAF
11 entriesAG
58 entries- Agabus
- Agape
- Agapetæ
- Agapetus
- Agapetus I, Pope Saint
- Agapetus II, Pope
- Agar, William Seth
- Agatha, Saint
- Agathangelus
- Agathias
- Agatho, Pope Saint
- Agaunum
- Agazzari, Agostini
- Agde, Council of
- Age, Canonical
- Age of Reason
- Agen, Diocese of
- Agents of Roman Congregations
- Aggeus
- Aggressor, Unjust
- Agiles, Raymond d’
- Agilulfus, Saint
- Agios O Theos
- Agnelli, Fra. Guglielmo
- Agnelli, Giuseppe
- Agnellus, Andreas, of Ravenna
- Agnellus of Pisa, Blessed
- Agnes of Assisi, Saint
- Agnes of Bohemia, Blessed
- Agnes of Montepulciano, Saint
- Agnes of Prague, Blessed
- Agnes of Rome, Saint and Martyr
- Agnesi, Maria Gaetana
- Agnetz
- Agnoetae
- Agnosticism
- Agnus Dei
- Agnus Dei (in Liturgy)
- Agonistici
- Agony, Archconfraternity of Holy
- Agony of Christ
- Agostini, Paolo
- Agostino Novello, Blessed
- Agoult, Charles Consstance César Joseph Matthieu d’
- Agra
- Agram
- Agrapha
- Agrarianism
- Agreda, Maria de
- Agria
- Agricius, Saint
- Agricola, Alexander
- Agricola, George
- Agricola, Rudolph
- Agrippa of Nettesheim, Heinrich Cornelius
- Agrippinus
- Aguas Calientes
- Aguirre, Joseph Saenz de
AH
2 entriesAI
16 entriesAJ
1 entryAK
3 entriesAL
241 entries- Alabama
- Alabanda
- Alabaster
- Alagoas
- Alagona, Pietro
- Alain de l’Isle
- Alalis
- Alaman, Lucas
- Alamanni, Niccolò
- Alan of Tewkesbury
- Alan of Walsingham
- Alanus de Rupe
- Alarcón, Pedro Antonio de
- Alaska
- Alatri
- Alb
- Alba Pompeia, Diocese of
- Alban, Saint
- Albanenses
- Albani
- Albania
- Albano
- Albany
- Albenga
- Albergati, Niccolo
- Alberic of Monte Cassino
- Alberic of Ostia
- Albero de Montreuil
- Alberoni, Giulio
- Albert Berdini of Sarteano, Blessed
- Albert, Bishop of Riga
- Albert, Blessed (Patriarch of Jerusalem)
- Albert II, Archbishop of Magdeburg in Saxony
- Albert of Aachen
- Albert of Brandenburg
- Albert of Castile
- Albert of Saxony
- Albert of Stade
- Albert, Saint
- Alberta and Saskatchewan
- Alberti, Leandro
- Alberti, Leone Battista
- Albertini, Nicolò
- Albertrandi, John Baptist
- Albertus Magnus, Saint
- Albi (Albia), Archdiocese of
- Albi, Council of
- Albi, Juan de
- Albicus, Sigismund
- Albigenses
- Albinus
- Albrechtsberger, Johann G.
- Albright Brethren, The
- Alcalá, University of
- Alcántara, Military Order of
- Alcedo, Antonio de
- Alchemy
- Alciati, Andrea
- Alcimus
- Alcmund, Saint
- Alcock, John
- Alcoholism
- Alcuin
- Aldegundis, Saint
- Aldersbach
- Aldfrith
- Aldhelm, Saint
- Aldric, Saint
- Aldrovandi, Ulissi
- Alea, Leonard
- Alegambe, Philippe
- Alegre, Francisco Xavier
- Alemany, Joseph Sadoc
- Alenio, Guilio
- Aleppo
- Ales and Terralba
- Alessandria della Paglia
- Alessi, Galeazzo
- Alessio
- Alexander Briant, Blessed
- Alexander I, Pope Saint
- Alexander II, Pope
- Alexander III, Pope
- Alexander IV, Pope
- Alexander (Name of Seven Men)
- Alexander (Name of Several Early Bishops)
- Alexander Natalis
- Alexander of Abonoteichos
- Alexander of Hales
- Alexander of Lycopolis
- Alexander, Saint (Bishop of Comana)
- Alexander, Saint (Of Cappadocia and Jerusalem)
- Alexander, Saint (Patriarch of Alexandria)
- Alexander Sauli, Blessed
- Alexander V
- Alexander VI, Pope
- Alexander VII, Pope
- Alexander VIII, Pope
- Alexandre, Dom Jacques
- Alexandria
- Alexandria, Councils of
- Alexandria, The Church of
- Alexandrian Library, The
- Alexandrine Liturgy, The
- Alexandrinus, Codex
- Alexian Nuns
- Alexians
- Alexis Falconieri, Saint
- Alexius, Saint
- Alfield, Venerable Thomas
- Alfieri, Count Vittorio
- Alfieri, Pietro
- Alfonso de Zamora
- Alfonso of Burgos
- Alford, Michael
- Alfred the Great
- Alfrida, Saint
- Alfwold, Saint
- Alger of Liége
- Alghero
- Algiers
- Algonquins
- Alife
- Alighieri, Dante
- Alimentation
- Alimony
- Aliturgical Days
- All Hallows College
- All Saints’ Day
- All Souls’ Day
- Allah
- Allahabad
- Allard, Paul
- Allatius, Leo
- Allegranza, Joseph
- Allegri, Antonio
- Allegri, Gregorio
- Alleluia
- Allemand, Jean
- Allen, Edward Patrick
- Allen, Frances
- Allen, George
- Allen, John
- Allen, John
- Allen, William
- Allerstein, August
- Alliance, Holy
- Allies, Thomas William
- Allioli, Joseph Franz
- Allison, William
- Allocution
- Allori
- Allot, William
- Allouez, Claude
- Alma
- Alma Redemptoris Mater
- Almagro, Diego de
- Almedha, Saint
- Almeida, John
- Almeria
- Almici, Camillo
- Almond, John
- Almond, John, Venerable
- Almond, Oliver
- Alms and Almsgiving
- Alnoth, Saint
- Alogi
- Aloysius Gonzaga, Saint
- Alpha and Omega
- Alpha and Omega (in Scripture)
- Alphabet, Christian Use of the
- Alphege, Saint
- Alphonsus Liguori, Saint
- Alphonsus Rodriguez, Saint
- Alpini, Prospero
- Alsace-Lorraine
- Altamirano, Diego Francisco
- Altamura and Acquaviva
- Altar Bell
- Altar Breadboxes
- Altar Breads
- Altar Candles
- Altar Candlesticks
- Altar Canopy
- Altar Cards
- Altar Carpets
- Altar Cavity
- Altar Cloths
- Altar Crucifix
- Altar Curtain
- Altar, Double
- Altar Frontal
- Altar, High
- Altar, History of the Christian
- Altar Horns
- Altar (in Liturgy)
- Altar Lamp
- Altar Lanterns
- Altar Ledge
- Altar Linens
- Altar of Our Lady
- Altar of Repose
- Altar, Portable
- Altar, Privileged
- Altar Protector
- Altar Rail
- Altar Screen
- Altar Side
- Altar Steps
- Altar Stole
- Altar Stone
- Altar, Stripping of an
- Altar Tomb
- Altar Vase
- Altar Vessels
- Altar Wine
- Altarage
- Altarpiece
- Altars (in Scripture)
- Altars (in the Greek Churches)
- Altmann, Blessed
- Alto, Saint
- Alton
- Altoona
- Altruism
- Alumbrados
- Alumnus
- Alunno, Niccolò
- Alva, The Duke of
- Alva y Astorga, Pedro d’
- Alvarado, Alonzo de
- Alvarado, Fray Francisco de
- Alvarado, Pedro de
- Alvarez, Balthazar
- Alvarez de Paz
- Alvarez, Diego
- Alvarez, Manoel
- Alvarus Pelagius
- Alypius, Saint
- Alzate, José Antonio
- Alzog, Johann Baptist
AM
83 entries- Ama
- Amadeo, Giovanni Antonio
- Amadia and Akra
- Amalarius of Metz
- Amalberga, Saint
- Amalberga, Saint
- Amalec
- Amalfi
- Amalricians
- Amalricus Augerii
- Amandus, Saint
- Amasia
- Amastris
- Amat, Thaddeus
- Amathus
- Amazones, Diocese of
- Ambarach, Peter
- Ambition
- Ambo
- Ambo (in the Russian and Greek Church)
- Amboise, George d’
- Ambronay, Our Lady of
- Ambros, August Wilhelm
- Ambrose of Camaldoli, Saint
- Ambrose of Sienna, Blessed
- Ambrose, Saint
- Ambrosian Basilica
- Ambrosian Chant
- Ambrosian Hymnography
- Ambrosian Library
- Ambrosian Liturgy and Rite
- Ambrosians
- Ambrosiaster
- Ambulatory
- Amelia
- Amelote, Denis
- Amen
- Amende Honorable
- Amerbach, Veit
- America
- America, Pre-Columbian Discovery of
- American College at Louvain, The
- American College in Rome, The
- American College in Rome, The South
- American Protective Association, The
- Amerigo Vespucci
- Amherst, Francis Kerril, D.D.
- Amias, Ven. John
- Amiatinus, Codex
- Amice
- Amico, Antonio
- Amico, Francesco
- Amida
- Amiens, Diocese of
- Amiot, Joseph Maria
- Amisus
- Ammen, Daniel
- Ammon
- Ammon, Saint
- Ammonian Sections
- Ammonites
- Amorbach
- Amorios
- Amorrhites
- Amort, Eusebius
- Amos
- Amovibility
- Amoy
- Ampè, André-Marie
- Amphilochius of Iconium
- Amphilochius of Sida
- Amphoræ
- Ampleforth, The Abbey of
- Ampullæ
- Ampurias
- Amra
- Amrah
- Amraphel
- Amsterdam
- Amulet
- Amulets, Use and Abuse of
- Amyclae
- Amyot, Jacques
AN
214 entries- Anæsthesia
- Anabaptists
- Anacletus II
- Anacletus, Pope Saint
- Anagni
- Analogy
- Analysis
- Anaphora
- Anarchy
- Anastasia, Saint
- Anastasiopolis
- Anastasius Bibliothecarius
- Anastasius I, Pope Saint
- Anastasius II, Pope
- Anastasius III, Pope
- Anastasius IV, Pope
- Anastasius, Saint
- Anastasius, Saint
- Anastasius Sinaita, Saint
- Anathema
- Anathoth
- Anatolia, Saint
- Anatolia, Saint
- Anatolius, Saint
- Anatolius, Saint
- Anatomy
- Anazarbus
- Añazco, Pedro de
- Anchieta, Joseph
- Anchor (as Symbol), The
- Anchorites
- Ancient of Days
- Ancilla Dei
- Ancona and Umana
- Ancona, Ciriaco d’
- Ancren Riwle
- Ancyra
- Ancyra, Councils of
- Andalusia
- Andechs
- Anderdon, William Henry
- Anderledy, Anthony Maria
- Anderson, Henry James
- Anderson, Lionel Albert
- Anderson, Patrick
- Anderton, James
- Anderton, Roger
- Anderton, Thomas
- Anderton, Venerable Robert
- Andlaw, Heinrich Bernhard, Freiherr von
- Andlaw, Venerable William
- Andrada, Alonso
- Andrada, Antonio de
- Andrada de Payva, Diego
- André, Bernard
- André, Yves Marie
- Andrea Dotti, Blessed
- Andrea, Giovanni d’
- Andrea Pisano
- Andreas of Caesarea
- Andreas of Ratisbon
- Andreas, Saint
- Andreis, Felix de
- Andres, Juan
- Andrés, Juan
- Andrew Avellino, Saint
- Andrew Bobola, Saint
- Andrew Corsini, Saint
- Andrew of Crete, Saint
- Andrew of Lonjumeau
- Andrew of Rhodes
- Andrew, Saint (Apostle and Martyr)
- Andrew, Saint (Martyr of Lampsacus)
- Andrew the Scot, Saint
- Andrews, William Eusebius
- Andria, Diocese
- Andronicus, Probus, and Tarachus, Saints
- Anemurium
- Anerio, Felice
- Anerio, Giovanni Francesco
- Anfossi, Filippo
- Ange de Saint Joseph
- Ange de Sainte Rosalie
- Angel
- Angel, Guardian
- Angela Merici, Saint
- Angela of Foligno, Blessed
- Angeli, Francesco degli
- Angeli, Girolamo degli
- Angelicals, The
- Angelico, Fra
- Angelo Carletti di Chivasso, Blessed
- Angelo Clareno da Cingoli
- Angels, Early Christian Representations of
- Angels of the Churches
- Angelus
- Angelus Bell
- Angelus, Silesius
- Anger
- Angers
- Angers, University of
- Anges, Notre Dame de
- Angilbert, Saint
- Angiolini, Francesco
- Anglesea, The Priory of
- Anglican Orders
- Anglicanism
- Anglin, Timothy Warren
- Anglo-Saxon Church, The
- Anglona-Tursi
- Angola and Congo
- Angora
- Angoulême
- Angra
- Angulo, Pedro
- Anhalt
- Anicetus, Pope Saint
- Anima Christi
- Anima, College and Church of the, in Rome
- Animals, Cruelty to
- Animals in Christian Art
- Animals in the Bible
- Animism
- Animuccia, Giovanni
- Anise
- Anna
- Anna Comnena
- Annals, Ecclesiastical
- Annas
- Annat, François
- Annates
- Anne d’Auray, Sainte
- Anne de Beaupré, Sainte
- Anne de Xainctonge, Venerable
- Anne Line, Saint
- Anne-Marie Javouhey, Venerable
- Anne, Saint
- Annecy
- Annegarn, Joseph
- Annibaldi, Annibale d’
- Annibale, Giuseppe d’
- Annius of Viterbo
- Anno, Saint
- Annunciation of the Blessed Virgin Mary, The Fact of the
- Annunciation of the Blessed Virgin Mary, The Feast of the
- Annunciation, The Orders of the
- Anointing of the Sick
- Anquetil, Louis-Pierre
- Ansaldi, Casto Innocenzio
- Ansaloni, Giordano
- Anschar, Saint
- Anse, Councils of
- Ansegisus
- Ansegisus, Saint
- Anselm of Laon
- Anselm of Liège
- Anselm of Lucca (the Younger), Saint
- Anselm, Saint
- Anselm, Saint
- Anselme, Antoine
- Anslo, Reyer
- Anstey, Thomas Chisholm
- Antediluvians
- Anterus, Pope Saint
- Anthelmi, Joseph
- Anthemius
- Anthony of Padua, Saint
- Anthony of Sienna
- Anthony of the Desert, Saint
- Anthony of the Mother of God
- Anthony, Orders of Saint
- Anthropomorphism, Anthropomorphites
- Antichrist
- Antidicomarianites
- Antidoron
- Antigonish
- Antimensium
- Antinoe
- Antinomianism
- Antioch
- Antioch, The Church of
- Antiochene Liturgy
- Antiochus of Palestine
- Antipater of Bostra
- Antipatris
- Antiphellos
- Antiphon
- Antiphon, Communion
- Antiphon (in Greek Liturgy)
- Antiphon (in the Greek Church)
- Antiphonary
- Antiphonary, Gregorian
- Antipodes
- Antipope
- Antiquities, Biblical
- Antivari
- Antofogaste
- Antoine, Paul Gabriel
- Anton Ulrich
- Antonelli, Giacomo
- Antonelli, Leonardo
- Antonelli, Nicolò Maria
- Antoniano, Giovanni
- Antoniano, Silvio
- Antoniewicz, Charles
- Antoninus Pius
- Antoninus, Saint
- Antonio Maria Zaccaria, Saint
- Antonio of Vicenza, Maria
- Antonius
- Antony, Franz Joseph
- Antwerp
- Anunciación, Fray Domingo de la
- Anunciación, Fray Juan de la
AO
1 entryAP
69 entries- Apaches
- Apameia
- Aparisi y Guijarro, Antonio
- Apelles
- Aphian, Saint
- Aphraates
- Apiarius of Sicca
- Apocalypse, Book of
- Apocatastasis
- Apocrisiarius
- Apocrypha
- Apocrypha (Notes)
- Apodosis
- Apollinarianism
- Apollinaris
- Apollinaris Claudius, Saint
- Apollinaris, Saint
- Apollinaris (the Elder)
- Apollonia, Saint
- Apollonius of Ephesus
- Apologetics
- Apolysis
- Apolytikion
- Apophthegmata Patrum
- Aporti, Ferrante
- Apostasy
- Apostle (in Liturgy)
- Apostle Spoons
- Apostles, Acts of the
- Apostles’ Creed
- Apostles of Erin, The Twelve
- Apostles, Portraits of the
- Apostles, The
- Apostleship of Prayer, The
- Apostolic Blessing
- Apostolic Camera
- Apostolic Church-Ordinance
- Apostolic Churches
- Apostolic College
- Apostolic Constitutions
- Apostolic Executor
- Apostolic Expeditors
- Apostolic Fathers, The
- Apostolic Letters
- Apostolic Majesty
- Apostolicæ Sedis Moderationi
- Apostolic See, The
- Apostolicæ Servitutis
- Apostolic Succession
- Apostolic Union of Secular Priests, The
- Apostolicae Curae
- Apostolici
- Apostolici Ministerii
- Apostolici Regiminis
- Apostolicity
- Apostolicum Pascendi Munus
- Apotactics
- Apotheosis
- Apparitions
- Apparitor
- Appeal as from an abuse
- Appeals
- Appetite
- Approbation
- Appropriation
- Apse
- Apse Chapel
- Apsidiole
- Apt, Council of
AQ
8 entriesAR
143 entries- Arabia
- Arabia, Councils of
- Arabia, Vicariate Apostolic of
- Arabian School of Philosophy
- Arabici
- Arabissus
- Arad
- Aragon and Castile
- Aran, The Monastic School of
- Aranda, Council of
- Aranda, Philip
- Arason Jón
- Arator
- Araucania
- Araucanians
- Araujo, Antonio de
- Araujo, Francisco de
- Arawaks
- Arbieto, Ignacio de
- Arbitration
- Arbogast, Saint
- Arbroath, Abbey of
- Arbuthnott, Missal of
- Arca
- Arcachon, Our Lady of
- Arcadelt, Jacob
- Arcadiopolis
- Arcae
- Arcanum
- Arch
- Archæology, Christian
- Archæology, The Commission of Sacred
- Archange de Lyon
- Archbishop
- Archconfraternity
- Archdeacon
- Archdeacon, Richard
- Archdiocese
- Archelais
- Archeology, Christian
- Archer, James
- Arches, The Court of
- Archiereus
- Archimandrite
- Archinto, Filipo
- Architecture, Ecclesiastical
- Architecture, Gothic
- Archives, Ecclesiastical
- Archontics
- Archpriest
- Archpriest Controversy
- Arcosolium
- Arculf
- Ardagh
- Ardbraccan
- Ardchatten, The Priory of
- Arden, Edward
- Ardilliers, Notre Dame des
- Aremberg, Prince Charles d’
- Areopolis
- Arequipa, Diocese of
- Arethas of Caesarea
- Arethusa
- Arévalo, Faustino
- Arévalo, Rodríguez Sanchez de
- Arezzo
- Argenson, Pierre de Voyer d’
- Argentina
- Argos
- Argüello, Luis Antonio
- Argyll and the Isles, Diocese of
- Argyropulos, John
- Arialdo, Saint
- Arianism
- Ariano
- Arias de Avila, Pedro
- Arias, Francis
- Arias Montanus, Benedictus
- Ariassus
- Aribo
- Arindela
- Ariosto, Ludovico
- Aristeas
- Aristides
- Aristotle
- Arius
- Arizona
- Ark, Noah’s
- Ark of the Covenant
- Arkansas
- Arlegui, Fray José
- Arles, The Synods of
- Armada, The Spanish
- Armagh
- Armagh, The Book of
- Armagh, The School of
- Armagnac, Georges d’
- Armellino, Mariano
- Armenia
- Armenierstadt
- Armentia, Fray Nicolás
- Armidale
- Arminianism
- Arnauld
- Arne, Thomas Augustine
- Arni Thorlaksson
- Arnobius
- Arnold
- Arnold of Brescia
- Arnoldi, Alberto
- Arnoldi, Bartholomaeus
- Arnolfo di Cambio
- Arnoudt, Peter Joseph
- Arnpeck, Veit
- Arnulf of Bavaria
- Arnulf of Lisieux
- Arnulf of Metz, Saint
- Arras
- Arras, Councils of
- Arriaga, Pablo José
- Arricivita, Juan
- Arrighetti, Nicola
- Arrighetti, Nicolò
- Arrowsmith, Venerable Edmund
- Arsacidæ
- Arsenius Autorianos
- Arsenius, Saint
- Arsinoe
- Art, Christian
- Art, Ecclesiastical
- Artemon
- Arthur, James
- Arthur, Thomas
- Articles of Faith
- Articles, The Organic
- Artoklasia
- Arts, Bachelor of
- Arts, Master of
- Arts, The Faculty of
- Arts, The Seven Liberal
- Artvin
- Arundel, Thomas
- Arundell
AS
70 entries- Asaph, Saint
- Ascalon
- Ascelin
- Ascendente Domino
- Ascension
- Ascension, Feast of the
- Ascetical Theology
- Asceticism
- Aschbach, Joseph, Ritter von
- Ascoli-Piceno
- Ascoli, Satriano, and Cirignola
- Aseity
- Aseneth
- Aser
- Asgaard
- Ash Wednesday
- Ashby, George
- Ashby, Thomas
- Ashes
- Ashley, Venerable Ralph
- Ashton, John
- Ashton, Venerable Roger
- Asia
- Asia Minor
- Asiongaber
- Aske, Robert
- Asmodeus
- Aspendus
- Asperges
- Aspilcueta, Martin
- Ass, The, in Caricature of Christians
- Assam
- Assemani
- Assemblies of the French Clergy
- Asser, John
- Asses, Feast of
- Assessor of the Holy Office
- Assessors
- Assicus, Saint
- Assideans
- Assimilation, Physiological
- Assimilation, Psychological
- Assisi
- Assistant at the Pontifical Throne
- Assizes of Jerusalem
- Assmayer, Ignaz
- Association of Ideas
- Association of Priestly Perseverance
- Association, Right of Voluntary
- Associations, Pious
- Assuerus
- Assumption, Augustinians of the
- Assumption, Little Sisters of the
- Assumption of Mary
- Assumption, Sisters of the
- Assumptionists
- Assur (multiple definitions)
- Assur (titular see)
- Assyria
- Assyrian Rite
- Asterisk
- Asterius
- Asti
- Aston
- Astorga
- Astrology
- Astronomy
- Astronomy in the Bible
- Astros, Paul-Thérèse-David d’
- Astruc, Jean
AT
41 entries- Atahuallpa
- Atahualpa, Jean Santos
- Atavism
- Athabasca
- Athanasian Creed, The
- Athanasius, Saint
- Atheism
- Athelney, The Abbey of
- Athenagoras
- Athenry
- Athens, Christian
- Athens, Modern Diocese of
- Athias, Joseph
- Athos, Mount
- Atienza, Juan de
- Atkinson, James
- Atkinson, Nicholas
- Atkinson, Paul, of St. Francis
- Atkinson, Sarah
- Atkinson, Ven. Thomas
- Atom
- Atomism
- Atonement, Day of
- Atonement, Doctrine of the
- Atrib
- Atrium
- Attainder
- Attala, Saint
- Attalia
- Attaliates, Michael
- Atticus
- Attigny, Councils of
- Attila the Hun
- Attiret, Jean Denis
- Atto
- Atto of Pistoia
- Atto of Vercelli
- Attracta, Saint
- Attributes, Divine
- Attrition
- Attuda
AU
69 entries- Aubarède, Jean-Michel-d’Astorg
- Aubermont, Jean-Aontoine d’
- Aubery, Joseph
- Aubignac, François Hédelin, Abbé d’
- Aubusson, Pierre d’
- Auch
- Auckland
- Auctorem Fidei
- Audiences, Pontifical
- Audifax, Abachum, Martha, and Maris, Saints
- Audiffredi
- Audin, J.-M.-Vincent
- Audisio, Guglielmo
- Auditor
- Audran
- Auenbrugger, Leopold
- Aufsees, Jobst Bernhard von
- Auger, Edmond
- Augilæ
- Augsburg
- Augsburg, Synods of
- Augusta
- Augustin von Alfeld
- Augustine of Canterbury, Saint
- Augustine of Hippo, Saint
- Augustine of Hippo, Teaching of Saint
- Augustine of Hippo, Works of Saint
- Augustine, Rule of Saint
- Augustinian Canons
- Augustinians
- Augustinians of the Assumption
- Augustinus, Antonius
- Augustinus-Verein, The
- Augustopolis
- Augustus
- Augustus Abbey, Fort
- Aulne Abbey
- Aumbry
- Aunarius, Saint
- Aurea
- Aurelian
- Aureliopolis
- Aurelius
- Aurelius Antoninus, Marcus
- Aureoli, Petrus
- Auriesville
- Aurispa, Giovanni
- Aurora Lucis Rutilat
- Ausculta Fili
- Ausonius, Decimus Magnus
- Austin, John
- Australia
- Austremonius, Saint
- Austro-Hungarian Monarchy, The
- Authentic
- Authenticity of the Bible
- Authority, Civil
- Authorized Version, The
- Autocephali
- Autos Sacramentales
- Autpert, Ambrose
- Autran, Joseph
- Autun
- Auxentius, Junior
- Auxentius of Milan
- Auxentius of Mopsuestia
- Auxerre, Councils of
- Auxiliary Bishop
- Auxilius of Naples
AV
29 entries- Ava
- Avancini, Nicola
- Avarice
- Avatar
- Avaugour, Pierre du Bois, Baron d’
- Ave Maria
- Ave Maris Stella
- Ave Regina
- Avellino
- Avellino, Saint Andrew
- Avempace
- Avendano, Fernando
- Averbode
- Averroes
- Aversa, Diocese of
- Avesta, The
- Avesta, Theological Aspects of the
- Avicebron
- Avicenna
- Avignon
- Avignon, Councils of
- Avignon, University of
- Avila
- Avila, Francisco de
- Avila, Sancho de
- Avitus, Saint
- Aviz, Order of
- Avranches, Council of
- Avril, Philippe