Do you mean the word “mass” or what goes on there? The word comes from the phrase in latin “ite missa est” at the end of mass which we translate as ‘go you are sent forth’. In English missa became mass. In the old missals that we used to use that phrase was translated as ‘go, the mass is ended’ which wasn’t the original meaning and the response ‘deo gratias’ often made me think thank God, now I can go home and get out of these shoes.
Of course, the real significance of the mass is that, through the action of the priest, Jesus makes present for us, or applies to us, the grace of the sacrifice of His death on the cross and then He gives us His body and blood as food and drink. We are worshipping the Father with Jesus as members of His body on earth. In the Mass, first we praise God, then repent of our sins, listen to His word from the old and the new testaments, hear the readings explained and applied to our lives, join with the whole church on earth and in heaven as the priest says the words Jesus said at the last supper which changes the bread and wine into Himself whom we receive. This is our “altar call”. When we go up to communion and say Amen we are saying I believe this is Jesus, I accept Him as my savior, I would stake my life on it!
There is a really good book by Scott Hahn called The Lamb’s Supper that shows how the mass parallels the worship of God in heaven shown in the book of Revelations.
I hope this helps. It’s a long answer to a short question.
