individual,

"...that's our word..."

Sorry, mate, words are not entities that can be "owned" - they are subject to evolution of meaning, dictated by social mores.

Poirot,
I'm sorry but your defensive argument is water off a duck's back in my book. Just look at what happened or rather what you lot did to a word which harmlessly described a just as harmless state of either one's feeling or a group ? The word gay ! It meant lightheartedness & feeling unencumbered. You lot hijacked it & claimed yes, claimed it as yes again, "your" word.
You really should feel a tad hypocritical.

individual,

Words are not entities that can be "hijacked"...they are subject to evolution of meaning, dictated by social mores.

they are subject to evolution of meaning, dictated by social mores.
Poirot,
Yes, that is an extremely convenient way to talk one's way out of it. That's why history gets so distorted, especially when academics interpret it. The sad thing is that many succinct descriptions now require endless gobbledegook to describe things, events & people. This gobbledegook, invented by academia is what enables callous & devoid of integrity lawyers to persecute decent folk. Some politicians make use of it also.

Individual, to help you be informed, Google "Original meaning of the word Gay"

I believe that Individual is right and that Poirot is missing the point. Supporters of gay "marriage" are cannot argue that the meaning of "marriage" has already evolved; they are actually agitating for its meaning to be changed by legislation — for a new meaning to be foisted on all of us by decree.

Consider two related questions: (a) Should same sex couples have the same legal rights as traditional married couples including the right to call their relationship a marriage? (b) Should same sex couples have the same legal rights as traditional married couples provided that they use a word other than "marriage" to describe their relationship? I suspect that a huge majority would assent to (b) but that there would be no majority for (a). If this proved to be true, you could argue that the meaning of "marriage" has already evolved to include same sex relationships, or is likely to any time soon.
I'm sure that most people still regard a homosexual relationship as categorically different from a heterosexual one. Not inferior, not less acceptable — just different. And it's linguistically convenient to have different words to indicate categorically different things. We would strongly oppose any suggestion to drop the distinction between "son" and "daughter" — to argue that we might just as well call all our offspring "sons" because male and female children are, after all, of equal worth. The argument for retaining different category words for homosexual and heterosexual relationships is not as strong as it is for male and female offspring, but to many it's still pretty strong.

It's important, too, to note that the opposition of many Australians to changing the meaning of "marriage" has nothing to do with religion or any other kind of folk lore or myth; it's entirely to do with concern for our language.