As a noun, the word can refer to gender, but it usually connotes sexual and/or sensual physical experience. Although many of my young women friends in their forties refer to "having sex" as a casual experience, I think every sexual experience is quite different. Good sexual experience involves respect and care for the needs of one's partner. Without that mutual respect, it comes close to exploitation, and for me, that's unethical behavior by either partner.
At almost ninety-two, I remember my sexual/sensual experiences with great pleasure. I met a wonderful Frenchman when he was eighty-five and I was seventy-two. We had a wonderful eight years together, until he died in 1998 of a massive stroke. Anyone who believes that sexual/sensual enjoyment ends at the age of sixty is giving up too soon.
When I was eleven, my elder sister, at twenty-one, attempted to answer my questions about love and sex. She said, "There's nothing dirty about sex. It's wonderful when it's connected to love. Don't forget that. And remember, what's called a "dirty"joke is never funny." I never was able to laugh at a so-called "dirty joke" after that.