Homophile is a word widely used by those with same-sex attraction while the term homosexual was still used by psychiatrists and other mental health professionals in the diagnosis of these attractions as a mental disorder. It was widely held by the homophile community that the term homosexual over emphasized the physical aspects of a same-sex relationship and that homophile, -phile coming from the Greek word for love, drew a more accurate picture by having the emphasis on the emotional aspects of such a relationship. With the DSM no longer considering homosexuality as a disorder and the popularization of the word pedophile (meaning one who has sexual attraction to children), the term homosexual has become far more commonly used where the term homophile is rarely, if ever, used at all.
Well known homophile groups include Harry Hay's "The Mattachine Society" for gay men and the unaffiliated "Daughters of Bilitis" for lesbians.
I prefer to be called a homophile because I don't just have sex with my partner, I love him.