How Are Sex, Gender, and Gender Identity Defined?

Children begin to understand and express their gender identity early in life (Caring for Kids). Parents can support healthy gender identity development by loving and accepting their children through their developmental stages. Unconditional support will reduce the feelings of shame that may occur when a child isn’t able to express their gender identity. Understanding how important terms are defined will give parents and caregivers the knowledge to navigate resources related to gender development.


Below is a list of definitions from Caring for Kids.

  • Sex at birth: When children are born, sex is assigned based on external genitalia. A child who has a penis is said to be male. A child who has a vulva is said to be female. 
  • Gender identity: Gender identity is “who you know yourself to be”. It is important to know that gender identity exists on a spectrum. A person’s gender identity can be masculine, feminine, or other.
  • Gender expression: This is how you express your gender to others, whether through behavior, clothing, hairstyle, the name you choose to go by, etc. Words to describe someone’s gender expression could be “masculine,” “feminine,” “androgynous,” etc.
  • Sexual orientation: This refers to sexual or emotional attraction that one feels for another person.
  • Transgender: When a person’s gender identity is not the same as the assigned sex at birth, they may be referred to as “transgender” (often shortened to “trans”). For example, a child born with female genitalia may identify as a boy. A child may also say that they are not a boy or a girl, but just “themselves” because they don’t want their sexual characteristics to define who they are. Some cultures and Indigenous people use the term “two-spirit” to represent a person who embodies both a masculine and feminine spirit. Two-spiritedness has many subtleties of a spiritual and cultural nature.
  • Gender dysphoria: Describes the level of discomfort or suffering that can exist when there is conflict between the assigned sex at birth and gender identity. Some transgender children experience no distress about their bodies, while others may express significant discomfort. This distress can be more obvious as puberty begins and the body starts to change.

Series Navigation

The Developmentally Appropriate Parenting Series highlights several early childhood topics to support parents and caregivers who are caring for young children. Use the list below to navigate through each series topic:

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Picture: A young baby looks up at the camera.
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