When I use a word.... (Humpty Dumpty)

I have no problem with same sex couples living together, and equally no problem with them putting their relationship on a legal footing. What I do have a problem with is calling such a relationship a marriage. It ain't! Look it up - a marriage is by definition a union of a man and woman as husband and wife. You might just as well stick a notice on the side of an elephant saying "This is a giraffe". It doesn't alter the fact that it isn't. I suppose the problem is that it's difficult to think of another word to describe such a relationship, but that doesn't excuse the deliberate mangling of the English language.