This is a partial list of famous people who are confirmed to be gay, lesbian or bisexual. Famous people who are rumored to be gay, lesbian or bisexual, are not listed. The definition of sexual orientation varies and has changed over time; for example the word "gay" was not used to describe a person's sexual orientation until the mid 20th century. However, there has been a number of different words or slangs that have been used to describe sexual orientations since the mid-19th century. Several studies have found that much of the research about sexual orientation has failed to define the term at all, which made it difficult to find results of different studies. However, most definitions include a psychological component (such as a person's erotic desire) and/or a behavioral component (which is about a person's sexual partner/s). Some people prefer to simply follow their self-definition or identity .