http://www.merriam-webster.com/dictionary/ritual?show=1&t=1338646824
ritual: 1 : the established form for a ceremony; specifically : the order of words prescribed for a religious ceremony
2 a : ritual observance; specifically : a system of rites b : a ceremonial act or action c : an act or series of acts regularly repeated in a set precise manner
The mass is the epitome of a ritual.
It's performed the same every where and every time it's practiced. The words and actions of the priest in his performing of the mass to consecrate the eucharist must be the exact every time or it is invalid.
Turning to number 655 in the hymnal and singing "Bringing in the Sheaves" and then having the preacher ascend the pulpit and rail against those "Gawd awful Catholics" every Sunday is every bit as much a ritual as the Catholic Liturgy. Ritual itself is not categorically a bad thing. The major difference is that the Catholic Liturgy is itself a prayer of worship of God.
Peace be with you