78 terms, plainly explained
Glossary
Catholicism carries two thousand years of vocabulary, and nobody hands you the dictionary on the way in. Here it is — every term in plain English, no assumed knowledge.
78 terms
A
- Absolution
- The words by which a priest, acting in the person of Christ, declares a penitent’s sins forgiven in the sacrament of Confession.
- Adoration
- Prayer before the Blessed Sacrament exposed or reserved in the tabernacle; worship due to God alone.
- Advent
- The four-week season of waiting that opens the Church year, preparing for both the birth of Christ and His return.
- Advocate
- A title of the Holy Spirit (Greek Paraclete) — the one called alongside to help, comfort, and defend.
- Alleluia
- A Hebrew acclamation meaning “praise the Lord,” set aside entirely during Lent and returned with joy at Easter.
- Ambo
- The raised stand from which the Scriptures are proclaimed at Mass.
- Anamnesis
- The remembering at the heart of the Eucharist — not merely recalling the past, but making its saving power present.
- Angelus
- A prayer commemorating the Incarnation, traditionally prayed at six, noon, and six at the sound of a bell.
- Annunciation
- The angel Gabriel’s announcement to Mary that she would bear the Son of God, and her consent (Luke 1).
- Apostolic Succession
- The unbroken handing on of authority from the apostles to bishops through the laying on of hands.
- Ascension
- Christ’s return to the Father in glory, forty days after the Resurrection.
- Assumption
- The teaching that Mary, at the end of her earthly life, was taken up body and soul into heaven.
B
- Beatific Vision
- The direct sight of God in heaven — the final end and happiness of the human person.
- Beatitudes
- The eight blessings that open the Sermon on the Mount, describing the character of life in the Kingdom (Matthew 5).
- Blessed Sacrament
- The consecrated Eucharist — the Body and Blood of Christ — reserved in the tabernacle.
- Breviary
- The book of the Liturgy of the Hours, the Church’s daily cycle of psalms and prayers.
C
- Canon
- Greek for “rule.” Used both of the accepted list of biblical books and of Church law.
- Canonisation
- The Church’s formal declaration that a person is in heaven and may be publicly venerated as a saint.
- Catechism
- A systematic summary of Catholic doctrine; the Catechism of the Catholic Church (CCC) is the current reference text.
- Catechumen
- An unbaptised person preparing to be received into the Church.
- Chaplet
- A short devotional prayer counted on beads, such as the Chaplet of Divine Mercy.
- Charism
- A gift of the Holy Spirit given not chiefly for one’s own sake but for the building up of the Church.
- Chrism
- Consecrated oil used at Baptism, Confirmation, and Ordination.
- Communion of Saints
- The bond uniting all the faithful — on earth, in purgatory, and in heaven — in one body under Christ.
- Confession
- The sacrament in which sins are confessed to a priest and forgiven; also called Reconciliation or Penance.
- Confirmation
- The sacrament that seals the baptised with the gift of the Holy Spirit.
- Consecration
- The moment in the Mass when the bread and wine become the Body and Blood of Christ.
- Contrition
- Sorrow for sin. Perfect contrition arises from love of God; imperfect, from fear of its consequences.
- Council
- A formal assembly of bishops; an ecumenical council gathers the whole Church, as at Nicaea, Trent, and Vatican II.
- Creed
- A summary statement of faith. The Apostles’ and Nicene Creeds are the two most widely professed.
D
- Deacon
- An ordained minister of service, who may preach, baptise, and witness marriages, but does not celebrate Mass.
- Deposit of Faith
- The whole of revelation — Scripture and Tradition — entrusted to the Church to guard and hand on.
- Diocese
- The territory and community of the faithful entrusted to a bishop.
- Doctor of the Church
- A saint recognised for the outstanding value of their theological writing, such as Augustine or Teresa of Ávila.
- Dogma
- A truth of revelation definitively proposed by the Church as requiring the assent of faith.
- Doxology
- A short formula of praise to the Trinity, such as the Glory Be.
E
- Ecumenism
- The work of restoring unity among divided Christians.
- Epiclesis
- The invocation asking the Holy Spirit to transform the gifts of bread and wine at Mass.
- Epiphany
- The manifestation of Christ to the nations, celebrated in the visit of the Magi.
- Eschatology
- The theology of last things — death, judgement, heaven, hell, and the new creation.
- Eucharist
- From the Greek for “thanksgiving” — the sacrament of Christ’s Body and Blood, “the source and summit of the Christian life.”
- Exsultet
- The great Easter proclamation sung in the dark at the Vigil, before the Paschal candle.
G
- Genuflection
- Bending the right knee to the ground before the Blessed Sacrament, in reverence.
- Grace
- God’s free and undeserved gift of His own life, enabling us to respond to His call.
H
- Homily
- The preaching that follows the Gospel at Mass, breaking open the Scriptures just read.
- Hypostatic Union
- The union of the divine and human natures in the one person of Christ.
I
- Immaculate Conception
- The teaching that Mary was preserved free from original sin from the first moment of her conception.
- Incarnation
- God the Son taking on human flesh in Jesus Christ — the central mystery of the faith.
- Indulgence
- The remission of temporal punishment due to sin already forgiven, drawn from the treasury of the Church’s merits.
K
- Kerygma
- The core proclamation of the Gospel — Christ died, rose, and reigns — as first preached by the apostles.
L
- Laity
- All the baptised who are not ordained; those whose vocation is to sanctify the world from within.
- Lectio Divina
- “Divine reading” — a slow, prayerful method of reading Scripture: read, meditate, pray, contemplate.
- Lent
- The forty-day season of fasting, prayer, and almsgiving preparing for Easter.
- Liturgy
- The Church’s public worship, above all the Mass; literally “the work of the people.”
M
- Magisterium
- The teaching office of the Church, exercised by the pope and the bishops in communion with him.
- Martyr
- From the Greek for “witness” — one who bears witness to Christ by the giving of their life.
- Mass
- The Church’s central act of worship, in which the sacrifice of Calvary is made present and the faithful receive Communion.
- Monstrance
- The vessel in which the consecrated Host is displayed for adoration.
N
- Novena
- Nine consecutive days of prayer for a particular intention, echoing the nine days before Pentecost.
O
- Ordinary Time
- The counted weeks of the year outside the great seasons, when the Church walks through Christ’s public ministry.
- Original Sin
- The wounded condition of human nature inherited from the fall, healed by Baptism.
P
- Paschal Mystery
- The passion, death, resurrection, and ascension of Christ, understood as one saving act.
- Penance
- Both the sacrament of Confession and the acts of prayer, fasting, or charity that express repentance.
- Pentecost
- The descent of the Holy Spirit on the apostles fifty days after Easter; the birthday of the Church.
- Purgatory
- The final purification of those who die in God’s friendship but still need cleansing before entering heaven.
R
- Real Presence
- The Catholic teaching that Christ is truly, substantially present — body, blood, soul and divinity — in the Eucharist.
S
- Sacrament
- An outward sign, instituted by Christ, that effects the grace it signifies. There are seven.
- Sacramental
- A sacred sign, such as holy water or a blessing, that disposes us to receive grace but is not itself a sacrament.
- Sanctifying Grace
- The habitual gift of God’s own life in the soul, received at Baptism and restored in Confession.
- Solemnity
- The highest rank of liturgical feast, such as Easter, Christmas, or the Assumption.
T
- Theotokos
- Greek for “God-bearer” — the title given to Mary at the Council of Ephesus in 431.
- Transubstantiation
- The change of the whole substance of bread and wine into the Body and Blood of Christ, the appearances remaining.
- Triduum
- The three holiest days: Holy Thursday evening through Easter Sunday, celebrated as one liturgy.
V
- Vespers
- Evening Prayer in the Liturgy of the Hours.
- Viaticum
- Holy Communion given to the dying — “food for the journey.”
- Vigil
- A liturgy celebrated the evening before a feast, above all the Easter Vigil.
- Vocation
- God’s personal call — to marriage, holy orders, consecrated life, or the single life — through which one becomes holy.
- Vulgate
- St Jerome’s Latin translation of the Bible, the Church’s standard text for over a millennium.
No term matches that. Try a shorter word — or ask a harder question.
Still stuck on a word?
This glossary grows. If a term sent you here and you could not find it, the apologetics room takes the harder questions head-on, and the journal works through many of these ideas slowly.
Definitions here are written for newcomers and kept deliberately brief; they are not a substitute for the Catechism of the Catholic Church. Profess Your Faith is an independent lay project, not a parish or official Church body.
Common questions
What does the word 'catholic' actually mean?
It comes from the Greek katholikos, meaning universal or according to the whole. It was first used of the Church by Ignatius of Antioch around the year 107, long before any division between Catholic and other Christian bodies.
What is the difference between a dogma and a doctrine?
Doctrine is the broad body of the Church's teaching. A dogma is a specific truth of revelation that has been definitively proposed by the Church as requiring the assent of faith. All dogmas are doctrines, but not all doctrines are dogmas.
What is transubstantiation?
It is the Church's term for the change by which the whole substance of the bread and wine becomes the Body and Blood of Christ at the consecration, while the appearances of bread and wine — taste, colour, and texture — remain unchanged.
What is the difference between a sacrament and a sacramental?
The seven sacraments were instituted by Christ and actually effect the grace they signify. A sacramental, such as holy water, a blessing, or a rosary, is a sacred sign instituted by the Church that disposes us to receive grace but does not confer it.
What does CCC mean when it is cited?
CCC stands for the Catechism of the Catholic Church, the official summary of Catholic doctrine published in 1992. The number that follows a citation refers to a numbered paragraph in that text rather than to a page number.
What is the Magisterium?
The Magisterium is the teaching office of the Church, exercised by the pope and by the bishops in communion with him. Its role is to guard and faithfully interpret the deposit of faith found in Sacred Scripture and Sacred Tradition.
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