endosexism, Intersex Awareness, Intersex People, Intersex Traits, Questions and Answers, Short Messages

Biological and Anatomical Sex: Endosex, Intersex & Altersex

What is Biological or Anatomical Sex?

The biologic character or quality that distinguishes male, female, and intersex from each other as expressed by analysis of the person’s gonadal, morphologic (internal and external), chromosomal, and hormonal characteristics.

Biological Sex and Anatomical Sex. Also often shortened to just “Sex”: It is typically assigned, at birth, by the “authorities”, based on the appearance of our external genitals, gonads, sex chromosomes, and sex hormones. Our gender, gender expression, and sexual orientation are often assumed by these two things; even though our gender has nothing to do with our genitals, hormones, or chromosomes.

This strict division of male and female “sex” is often referred to as the “binary”.  However in nature and in reality there are many different types of bodies out there.  Way more than typical male or the typical female anatomy.

It is important to not conflate Biological or Anatomical sex with a person’s  gender identity and gender expression.  They do not always match and all people are valid in the way they describe themselves.  Any type of human, endosex, intersex, or altersex, can have a gender identity as man/boy, woman/girl, both or neither and the many ways to describe this.  

There are many ways a person can define their gender identity.  Anatomical and Biological Sex does not always define our gender identity, so out of respect always ask a person how they identify if you are not certain.


Bodily Variations

I prefer to use the word endosex to describe people who were not born intersex.  In the past “dyadic” was used for this same purpose. The very word “dyadic” implies that only two sex exist which is not accurate if we are to respect intersex existence.

Endosex is a way for the medical community to describe sex characteristics that categorize as typical anatomical females or males.  The human body has proven that there are many endosex variations.   At some point endosex variations can cross a subjective line and could now be considered “intersex”.  These articles might help to show where that endosex/intersex line is crossed:  1 : 150 Have Intersex Traits

Please note: Endosex people can have any gender identity, as man, woman, both and neither. This including the many ways to describe gender identity: transgender, non-binary gender, nonconforming gender, gender fluid, bi-gender, tri-gender, asexual, and all the many other ways.

Endosex Male: Is the physiological sex that produces sperm. Most male mammals, including male humans, have one Y and one X chromosomes.  I like to say “Endosex Male”.


Endosex Female: Is the sex of an organism, or a part of an organism, that produces non-mobile ova (egg cells). Most female mammals, including most female humans, have two X chromosomes.  I like to say “Endosex Female”.



Bodily Variations

Intersex is a general term used for bodily, hormonal, or chromosomal variations in which a person is born with reproductive or sexual anatomy that doesn’t seem to fit the typical definitions of endosex female or male.  I believe that all intersex variations are ideal for an intersex person and should never be considered a disorder, condition or birth defect unless that person is okay with that.  Please note that Intersex is now being defined as sex with many birth certificates now in the United States.

Some forms of intersex occur after birth and later in life. However, many of these are naturally occurring bodily variations too. In humans, it is a variation in sex characteristics, including chromosomes, hormones, gonads, or genitals that do not allow an individual to be considered as endosex male or female. That is because they were born an intersex person. If you are not born into an endosex/dyadic body, you would have a naturally occurring intersex body.

Just like anyone else, an intersex person can have any gender, sexual orientation, or gender expression. The “rules” of the heteronormative binary, male and female, often do not work for intersex people. Since intersex is a way to describe a person’s biological sex, it should not be confused as a gender identity. If a person’s gender identity matches their being intersex, I suggest they say they are “intergender” or “non-binary”, to not conflate sex with gender.

In the past, and in some countries, the term “hermaphrodite” is used to describe people born intersex. Depending on the country or the person, this can be considered offensive. Always ask, to make sure it is ok to use the word hermaphrodite. Please always ask if it is ok to say in your country. Some accept it, and some do not now.


Altersex: a catch-all term consisting of “alter”, meant here as “different” or “another possibility,” and sex, referring to physiological primary and secondary sex characteristics. Altersex refers to possible sexes that are neither endosex nor intersex, in the cases of those who go through HRT or sexual reassignment surgery of some sort to change their sex. Altersex is a word that can be used for people who are not born intersex, who alter their sex to appear intersex.

However, please take care if choosing to use this word.   If a person does alter their sex with surgery or hormones, it is expected that everyone is to respect their sex reassignment and never say that they are “altersex.”.  It is highly disrespectful not to honor their sex change, for they are valid in their true sex and true gender.

Sex Reassignment Surgery

The way I see it:  Both endosex or intersex people can have surgery to alter their sex from one sex to the other and they are valid in who they became in their new surgically made body.   Anyone that says otherwise is possibly transphobic and/or exclusionary and is not respecting informed consent and self-determination to transition surgically from one sex to another.  My biggest concern, as a Gender/INTERSEX Activist and educator is ending medically unnecessary cosmetic genital reproductive surgeries done on non-consenting intersex children.  This blog fights for the intersex child’s bodily autonomy, self-determination, and rights of the gender variant child.

To learn more on gender identity, sexual orientation and gender expression please go to the links below:

II. Gender Identity

III. Sexual Orientation

V. Gender Expression Words


My TEDx: Born Intersex: we are human! 

Please also visit the United Nations Intersex Fact Sheet PDF

Related Blogs: 


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