Taken from the United States Conference of Catholic Bishops website.
Altar
The altar is a special table on which the Eucharist is celebrated. In ancient times, it was a platform on which sacrifices were offered. As a result of liturgical changes implemented by the Second Vatican Council and the subsequent decrees instituted by the Holy See, altars once again face the congregation, are freestanding.
Altar Cloth
The piece of linen or other fabric which covers the altar.
Aspergillum
Instrument for sprinkling holy water.
Chalice
The cup or goblet used for the consecration of the wine in celebration of the Eucharist.
Ciborium
A vessel used to hold small Communion Hosts. IT resembles a chalice, but it is longer and has a lid. Also, it can refer to a dome-shaped canopy over an alter (otherwise known as a baldachino).
Corporal
A piece of white linen cloth, measuring about twenty inches square, placed on the altar and on which the bread and wine are placed and consecrated during Mass. Church custom dictates that the corporal be placed in the tabernacle beneath any vessel holding the Eucharist and, during Benediction or Eucharistic adoration, beneath the monstrance.
Cruets
Containers made of glass or pottery, which hold the wine and water we bring to the altar during Mass. When members of the community bring gifts to the altar, they carry the wine in a cruet. The second cruet contains water.
Crucifix
A cross with the image of Jesus on it. It reminds us that Jesus died to save us. It is the most solemn and significant symbol of the Christian faith, as it represents the absolute sacrifice made by Christ - his willingness to perish as a common criminal in order to grant his followers the opportunity to gain salvation.
Holy Oils
The Church uses three holy oils in the sacraments. The bishop blesses these oils at a special diocesan celebration and each parish receives some for us during that year.
Holy Chrism is the holiest of the oils and is scented with balm. It symbolizes spiritual strength. Chrism issued to anoint people in three of our Sacraments: Baptism, Confirmation, and Holy Orders.
Oil of the Catechumens is used in Baptism and is used in preparing adults who wanted to join the Catholic community.
Of the Sick is used in the sacrament of the Anointing of the Sick. The priest uses the oil to anoint a sick person on the forehead and on the palms of the hands.
Holy Water or Baptismal Font
The church building is a home for God's people, the Church. We enter by the front door and find a holy water font. We dip our fingers in the holy water and bless ourselves with the Sign of the Cross when we enter the church. This water and Sign of the Cross remind us that we became members of this church at our Baptism.
Hosts
Hosts are round pieces of bread ready for the priest to ask the Holy Spirit to change into the body of Christ. This bread is made of flour and water and baked in a special machine. When it is finished, the bread looks like a thick sheet of paper. The hosts are cut with a machine like a cookie cutter.
Incense and Censer
Small grains of incense, when placed on a burning piece of charcoal, give off a sweet-smelling smoke. People have used incense with their prayer for many centuries. We call incense a sacramental, a sign or a thing that helps us remember God. The bowl that holds the hot charcoal has long chains on it and is called the censer. The incense is sprinkled over the hot coals. The incense is kept in a little dish that is called an incense boat. During a service in which incense is used, the priest sprinkles a little incense on the burning coals. He then swings the censer as the smoke rises.
Lectionary
The book which contains the readings from the Bible that we hear during the Liturgy of the Word at Mass.
Paten
A saucer-like dish which holds the bread to be consecrated at Mass; it is usually gilded or silver-plated and must be large enough to cover the chalice. Patens traditionally are blessed by a bishop or his delegate.
Presider's Chair
The priest sits on this chair while he is leading us in prayer during Mass.
Purificator
A small towel used to clear the chalice.
Sacramentary
A book of prayers used during the Mass.
Sacristy/Sacred Vessels
The room where the priest keeps the vestments and sacred vessels. This room is next to the sanctuary. The piest gets ready for mass in the sacristy.
Stations of
the CrossThe Stations of the Cross tell the story of what happened to Jesus on Good Friday, the day he died on the cross. Usually a church has seven stations on one side wall and seven on the other side. Some churches have 15 stations. The 15th station reminds us that Jesus rose to new life on Easter.
Tabernacle
The tabernacle is a special box where the Hosts for Holy Communion are reserved in churches and chapels. The priest prays at the Mass that the Holy Spirit come upon these hosts and change them in to the body of Christ. The tabernacle is usually constructed of wood, stone, or metals, and is round or rectangular in shape. A tabernacle normally contains a ciborium for consecrated Hosts. It is located in the middle of the sanctuary or in a side chapel. A sanctuary lamp is kept nearby to call attention to the presence of the Blessed Sacrament.