Merlin said:
It is not just a word. It is the name of a holy sacrament. There are other secular words which are protected. You cannot call yourself a lawyer unless you are. You can call yourself a bank unless you meet certain criteria. So it is not alone in the word being more than a word but the name of an institution. It is this institution that people feel so strongly about.
Forgive me, I do not know the laws of your country. However, in the United States, the government can only regulate the use of words in commerce. For example, you cannot sell something as "low fat" unless it meets the criteria to do so. But I can call myself low fat, I can make a triple cheeseburger and call it low fat, as long as I am not selling it.
In the case of lawyers, you need a license to practice law professionally (ie: commercial purposes). However, you do not need any qualifications to represent yourself. In law, they are not even called "lawyers" but "legal council." You can consult with your retarded cousin for all they care, though they will probably advise against it.
There are a lot of banking regulations, although they are legally called "financial institutions." But if a piggy bank fits the criteria, then our regualtions are pathetic.
Notice how they use more specific words. This clears up alot of ambiguity, plus within the law they will define the terms as used within that law. A different law may define the term differently, and these definitions do not determine everyday use.
Even with the limited power that the government has over the words, none of these examples exhibit a "holy sacrament." The closest thing that I can come up with would be the use of the word "kosher." Could the federal government define what makes something kosher? If they do, they dictate that you cannot sell something called kosher without it meeting certain criteria. But, once again, this would not in anyway change what the Jews consider to be kosher. It would only apply to commerce.
Since marriage has nothing to do with commerce, the only conscern would be what it is called in the law. They can call it a "strategic tax alliance" or a "joint liability contractual obligation." It has been traditionally called marriage, and is considered such in the eyes of that law. For example, we could make a law that defines marriage as the union between a man and his dog, and the law could state that the man can void the marriage by taking his dog to an animal shelter. This would not effect the definition of a marriage as defined under any other law, nor would it effect the relationship between a man and his wife.
If the usage of a word is so important to a group of people, they need to request that a different word be used. The problem that we have here is that these people, since they hold the majority, wish to change the legal definition of the word. Our government has no business in regulating the qualification or procedures of religious ceremonies or sacraments. It baffles me why anybody would want to change that treasured separation.