"Our choice of words can determine whether the people we speak to perceive us as accepting and affirming or rejecting and hostile." 
Please note: Although definitions are provided here, it is important to keep in mind that in the area of sex, gender and sexual behaviour, the definitions and connotations associated with the words change over time and mean different things to different people. It is also important to separate behaviour from sexual and gender identity, to avoid labeling anyone and to respect the terms people use to define themselves.
Berdache: This is a North American First Nations term that refers to a person that is "usually biologically male, who effects a change in his or her gender status by adopting the clothing styles, occupations, and behaviours of the other sex."
Bi-gendered: someone who self-identifies with both maleness and femaleness and who lives part time as each, may be referred to as a cross-dresser
Bisexual: someone who engages in both same-sex and opposite-sex sexual behaviour
Cross-dresser: someone who dresses as the opposite sex but who has a heterosexual sexual orientation
Drag King: a woman who gender identifies with and/or acts out men’s social sex roles but does not pursue physical change
Drag Queen: a man who gender identifies with and/or acts out women’s social sex roles but does not pursue physical change
Dyke: this term used to be a derogatory term used for lesbians, however, some lesbians are reclaiming the label
Fag: a derogatory term for a homosexual person. This term has also been used as a militant gay identification.
Gay: denotes self-identification as homosexual. This term is often used within urban communities. It is usually applied to men but can also be used for women.
Gender Identity: the inner knowledge of being male or female
Gender Identity Disorder: a DSMIV diagnostic term replacing transsexualism and that encompasses transsexualism, gender identity disorder of childhood and gender indentity disorder of adulthood
Hermaphroditism: a form of intersexuality in which both ovarian and testicular tissue are present in either the same gonad or in opposite gonads. It is extremely rare.
Heterosexism: the belief or assumption that everyone is heterosexual and that heterosexuality is right and superior to homosexuality and results in the invisibility of anyone who doesn’t fit into the heterosexual norm. 
Heterosexual: someone who engages in opposite-sex sexual behaviour
Homophobia: an irrational fear, hatred or repulsion of homosexuality
Hijras: This is a religious group that is comprised of "biological men who wear female apparel and behave like women". Historically their penises and scrota would be surgically removed. Today, not all hijras undergo this surgery.
Homosexual: someone who engages in same-sex sexual behaviour. The term has clinical connotations associated with pathology and historically used in the context of illness and abnormal sexual behaviour
Internalized Homophobia: homophobic cultural messages, stereotypes and negative labels that are accepted and internalized by a gay, lesbian, bisexual or transgendered person
Intersex: the condition of having genital, gonadal, or chromosomal characteristics that are neither all "female" nor all "male"
Khush: Asian lesbian or gay man
Lesbian: a woman who self-identifies as homosexual
Lifestyle: a term that is sometimes used for sexual orientation, but it implies that being gay or lesbian is a lifestyle choice
Mahu: This is a traditional Tahitian term that describes a biological male that "takes on both the work and dress of a woman."
Nadle: a North American First Nations term that refers to the "gender status assigned to a person born with an ambiguous genital configuration". These people dress as males or females in the community depending on what kind of work they are doing at the time. They are also free to switch back and forth whenever they choose.
Pseudohermaphroditism: a state in which the individual is of an unambiguous gonadal sex (i.e. possesses either testes or ovaries) but has ambiguous external genitalia
Queer: some in the gay community now use this word as a political statement of pride in their sexual identity. This term was once a derogatory term used for gay men.
Sexual Identity: an individual’s self definition as gay, lesbian, bisexual or heterosexual. This is not necessarily congruent with sexual behaviour or orientation.
Sexual Orientation: a three-dimensional definition including desire, identity and sexual behaviour. It is important to remember that sexual orientation does not always correlate with sexual behaviour.
Straight: a common term referring to someone who engages in opposite-sex sexual behaviour
Transgendered: an individual who is a transsexual, cross-dresser, drag queen/king, biologically intersexed, or who otherwise challenges strict gender norms
Transsexual: someone who gender identifies with and/or lives as someone of the opposite biological sex, takes hormones and pursues sex reassignment surgery
Transsexual Man: FTM or female-to-male transsexual
Transsexual Woman: MTF or male-to-female transsexual
The Vowed Virgins of Albania: These are girls and women who choose to become the heads of their household when the man of their household dies and there is no other man to take his place. These women cut their hair short and live the rest of their lives doing the men’s work, socializing with men, and being treated like the men of the household. They never marry or have children.
WSW: a term to describe a woman who has sex with women. This is an epidemiological term referring only to behaviour and ignores the relationships, culture and beliefs of a self-identified gay woman .
Xanith: This is an Islamic term that refers to "males who enjoy all the rights of a man under the law, worship in mosques with other men, have male names, and are referred to with the use of masculine grammatical form. However, xanith perform the role of women within their households and their attractiveness is judged by standards of female beauty." They are segregated with women for the most festive occasions. Unlike both men and women of that culture, xanith go bareheaded and wear more perfume than either the women or the men. They are also male sexual partners for other men. Xanith may choose to change their status to male by marrying a woman and producing a bloodied handkerchief that proves the consummation of the marriage.
Zami: a word used by lesbians of African descent, meaning women who work together as friends and lovers
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