A hormone produce in the male body, which is similar in structure to testosterone, but which causes the person producing it to become increasingly homosexual in a proportion directly related to the amount of homosterone being produced.
The appearance of this hormone is especially apparent in males tending to wear clothes purchased at stores similar to, and including, Abercrombie, Hollister, and American Eagle.
This hormone may also be referred to by the less knowledgeable portion of the population as douchebagerone.
Matt: Wow Robert. With all the American Eagle clothing in your closet, your body must produce large quantities of homosterone.
Robert: Yup. It kinda makes me wanna wrestle with other men sometimes.