No, it comes from the Roman Missa or “sent”. It’s the last words of the whole celebration. “Go and spread the good news to the world”, or something to that effect. The Mass should be the beginning step in any mission we might undertake. Specifically, it is our first step in the first day of the mission to live in the world that next week.
The English word “Mass” is simply the result of how the word evolved in English over the centuries. The Catholic mass, like the mass in many other denominations contains multiple parts, called liturgies.
We have the Liturgy of reconciliation, where are asked to do a quick reflection of the ways we have not received God’s grace fully that week (or longer) and to ask to be healed (“Lord have Mercy, Christ have Mercy, Lord have mercy).
This is followed by the liturgy of the word, where we read from Old Testament, Palms and the Epistles and finally the Gospels, followed by a homily (not preaching), that is designed to help us to understand the readings we just attended to.
The next part is the Eucharist. This means celebration. Here, we celebrate the grace that was made available to us via the Death and resurrection of Jesus and we partake in a re-living of the last Supper where Christ said “Take and eat” and “Take and Drink” when he passed around the bread (His Body) and wine (His blood). This is the high part of the Mass.
Finally, comes the concluding rite, the dismissal, the part where that word “Mass (missa)” comes from. This rite ends with the priest sending us out on our mission to the world.
So Christ mass is referring to a celebration of the death and resurrection of Christ. But specifically, its celebrating the incarnation (birth) of Christ (God) into Human form.
“Christmas” means by definition “death of Christ”. The word Christmas comes from “Cristes Maesse”, an early English phrase that means “Mass of Christ.” It is interesting to note that the word “Mass”, as used by the Roman Catholics, has traditionally been rejected by the so-called Protestants, such as Lutherans, Baptists, Methodists, Presbyterians, Pentecostals and so on. The word “Mass” is strictly a Catholic word and thus, so is “Christ-Mass.” “Mass” in religious usage means a “death sacrifice.” In essence, the Mass is the ceremonial slaying of Jesus Christ over and over again, followed by the eating of his flesh and the drinking of his blood. The Mass is the death sacrifice, and the “Host” is the victim. This is official Roman Catholic doctrine, and “Christmas” is a word that they invented.
Though some teachings Mass does not mean death. It comes from the ending of the Mass in Latin, “Ite, Missa est.” This means “Go, you are sent.” “Missa” is the root word meaning “sending” that forms the basis of the word “transmission” and other such words.