Some terms in this area are contested but the following are provided to clarify the meanings used in these support materials. The definitions are current as at November 2007.

Discrimination is the practice of treating one person or group less fairly or less well than others. It can be direct or indirect.

Harassment is behaviour intended to trouble or annoy someone.

Sexuality is comprised of sexual orientation, sexual identity, and sexual behaviour.

• Sexual orientation refers to a person's enduring emotional or romantic attraction towards other people. Although this occurs on a continuum, several significant categories form, based around the sex or gender that the person finds most attractive. The term sexual orientation is largely favoured over sexual preference.
  • Heterosexual (or straight) refers to people whose sexual and romantic feelings are primarily for people of the opposite sex.
  • Homosexual (or gay and lesbian) refers to people whose sexual and romantic feelings are primarily for those of the same sex.
  • Bisexual (or bi) refers to people whose sexual and romantic feelings are for people of both sexes. Bisexual (or bi) refers to people who have the capacity for emotional, romantic, and or physical attraction to more than one gender/sex.
• Sexual identity is how we perceive and what we call ourselves regarding our own sexuality. Our sexual identity evolves throughout our lives in a developmental process that depends on the individual.
• Sexual behaviour refers to practices that people use when seeking sexual or relational partners. It may be develop with and be linked to, but not should be equated with, sexual identity or sexual orientation.

Gender refers to the socially constructed roles, behaviours and attributes a society or culture considers most appropriate or typical for a given gender. The concept of gender is made up of gender identity – a person's internal sense of being male, female or something in between – and gender expression – external characteristics and behaviours that are socially defined as masculine, feminine or both.

Coming out is the process of acknowledging one's gay, lesbian or bisexual attractions and identity to oneself and disclosing them to others.

Homophobia refers to fear or hatred of homosexuality and homosexual people, especially in others but also in oneself (internalised homophobia). A person who holds homophobic views or demonstrates such discrimination or harassment is said to be a homophobe.

Biphobia refers to a range of irrational, negative responses to bisexuality and bisexual people, especially in others but also in oneself (internalised biphobia). Frequently, biphobia is evident within gay and lesbian communities. A person who holds biphobic views or demonstrates such discrimination or harassment is said to be biphobic.

Queer is an historically negative term applied to people perceived to be non-heterosexual. It has recently been reclaimed by some people as a positive term to describe all people who may not conform to rigid notions of gender and sexuality.