Matrimony
Matrimony is just a fancy way of saying “marriage.” When a couple ties the knot, they are engaging in matrimony.
You can describe the actual wedding celebration as matrimony, and also the state of being married, although it’s a formal word most often used in documents and in the words of the ceremony. The Latin word for matrimony is matrimonium, which comes from combining mater, “mother,” with the suffix monium, “action or condition The term highlights the extent to which reproduction and childrearing are central to marriage itself. As the Code of Canon Law notes (Canon 1055), “The matrimonial covenant, by which a man and a woman establish between themselves a partnership of the whole of life, is by its nature ordered toward the good of the spouses and the procreation and education of offspring.”
‘Technically, matrimony is not simply a synonym for marriage. As Fr. John Hardon notes in his Modern Catholic Dictionary, matrimony “refers more to the relationship between husband and wife than to the ceremony or the state of marriage.” That is why, strictly speaking, the Sacrament of Marriage is the Sacrament of Matrimony. Throughout the Catechism of the Catholic Church, the Sacrament of Marriage is referred to as the Sacrament of Matrimony.
The term matrimonial consent is often used to describe the free willingness of a man and a woman to enter into marriage. This stresses the legal, contract or covenant aspect of marriage, which is why, besides being used to signify the Sacrament of Marriage, the term matrimony is still widely used today in legal references to marriage.