(This list is not comprehensive and may not apply to every individual.)
Androgynous: a term for a person who expresses or presents merged socially-defined masculine and feminine characteristics, or mainly neutral characteristics.
Crossdressing: dressing as someone from a different gender category; may be done by people from all genders and sexual orientations. Crossdressers sometimes refered to as transvestites.
Drag: crossdressing, especially in public or in a performance.
Female-To-Male (FTM), Male-To-Female (MTF): used to classify crossdressers, transgender individuals, or transsexuals; may indicate either gender expression or gender identity.
Feminine: concept of what is "naturally" or traditionally female in terms of appearance, behavior, and personality.
Gender: gender covers a wide range of issues that affect everyone. Subcategories of gender include: Gender Characteristics--characteristics that are used by others to attribute gender to an individual, such as facial hair or vocal pitch; Gender Expression/Gender Presentation--the way a person expresses his or her gender through gestures, movement, dress, and grooming; Gender Identity--a person's understanding, definition, or experience of their own gender, regardless of biological sex; Gender Nonconformity--not expressing gender or not having gender characteristics or gender identity that conform to the expectations of society and culture; Gender Role--culturally accepted and expected behavior associated with biological sex.; Gender Binary System--a social system that requires that everyone be raised as a boy or girl (dependent on what sex you are assigned at birth) which in turn forms the basis for how you are educated, what jobs you can do (or are expected to do), how you are expected to behave, what you are expected to wear, what your gender & gender presentation should be, and who you should be attracted to/love/marry, etc.
Intersex: refers to someone who is biologically neither completely male nor completely female; may have genital and/or reproductive body parts of both sexes. Visit www.isna.org  for more information about intersex issues.
Masculine: concept of what is "naturally" or traditionally male in terms of appearance, behavior, and personality.
Passing: crossdressing well enough to be seen as a member of a different sex/gender category.
Sex: one's biological assignment as male, female, or intersexed.
Transgender (TG): a term for designating those who transcend or transgress gender by not looking, acting, being, or identifying as traditionally male or female; can include crossdressers, transsexuals, intersex people, and other gender nonconformists.
Transsexual (TS): a person who feels that his or her gender identity does not match their biological sex ("I'm a woman in a man's body" etc.); a pre-op (preoperative) transsexual is a TS preparing to have sex reassignment surgery, and a post-op (postoperative) transsexual has already undergone sex reassignment, although not all transsexuals desire surgery; some transsexuals take hormones to make their bodies look more male or female.
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