You can't use the dictionary because it's too general. It's not specific to anything at all. It's a dictionary!
Can you, or can you not prove gay sex is natural?
We do not want word to go out that we want to exterminate the Negro population. – Margaret Sanger, founder of Planned Parenthood, 1939
RamFel, you have had shown to you that with any definition from the dictionary or that you have provided, gay sex qualifies as natural. You have in fact offered a total of zero evidence that it is not natural. Your continued denial of all this is sad.
Gay sex is unnatural because it has no potential for procreation. Natural sex can make babies, and unnatural sex cannot.
I don't have to look that up in a book because everybody knows that when hetero couples mate, a baby is born (unless they don't want one). Gays can't make a baby at all...not at all...unless and until they engage in natural sex.
But if you have something better, something that proves that I'm wrong, then I'm all ears.
Procreation is not a guaranteed possibility just because a couple is a man and a woman.
"A woman is like a teabag, you never know how strong she is until she gets in hot water." - Eleanor Roosevelt
Keep your religion out of other people's marriages.