This is actually false, the definition of this word is lost to history. The churches have always wanted it to mean homosexual, and it seems plausible enough, so they went with it. But among the few other occurences of it in ancient literature, one is a church father complaining about men committing it with their wives, and another is in a myth about pagan gods with no sexual context. But there were plenty of other common words to describe sexual relations, including homosexual ones.