SPROUT Program Glossary

Understanding the complex world of sex development can be challenging. To help you navigate this topic, we've compiled a glossary of key terms and definitions. This list is designed to clarify the language and concepts commonly used in discussions about sex development, providing clear explanations for terms related to hormones, chromosomes, genitalia, and more. 

Androgens: A group of hormones that cause body changes similar to the changes caused by testosterone (see below). 

Chromosomes: Tiny packages of genetic instructions that tell your body how to grow and develop. Chromosomes are found in every single cell of your body. Chromosomes are tested through a special blood test called a karyotype. Most people have 46 chromosomes, but some people have more or less. There are two chromosomes called the X and Y chromosomes that have special instructions on how to build the reproductive system – we name these chromosomes separately when we are talking about a person’s chromosome pattern. The most common pattern of chromosomes for females is 46,XX, and the most common pattern for males is 46,XY, but there are lots of other patterns too.  

Estrogen: A puberty hormone that causes body changes like breast development, wider hips, and periods or menstrual cycles.  

External genitalia: This refers to the parts of the reproductive system that you can see from outside the body. These parts might include the vulva, labia, clitoris, penis, or scrotum.  

Gonads: Small organs in the abdomen or pelvis that are important for puberty and reproduction. Some types of gonads are ovaries (these usually produce estrogen and eggs), testes (these usually produce testosterone and sperm), ovotestes (this is a gonad that is made of both ovarian and testicular tissue), and streak gonads or dysgenetic gonads (these may not produce the usual amounts of hormones or eggs/sperm).  

Hormones: Chemical signals that travel from one part of your body through the blood vessels to other parts of your body and tell the different parts of your body how to grow and work together. 

Internal genitalia: This refers to the parts of the reproductive tract that you can’t see from outside the body. These parts might include the gonads (in some cases), the uterus, fallopian tubes, vas deferens, prostate, epididymis.  

Nonbinary genitalia: External genitalia that doesn’t look like the typical male appearance or the typical female appearance. Other words that are sometimes used to describe genitalia like this include “atypical” or “ambiguous.” For example, a baby may have hypospadias (where the opening for urine is not at the tip of the penis) and undescended testes or a baby may have an enlarged clitoris and labia that are enlarged and partially fused together. 

Testosterone: A puberty hormone that causes body changes like deeper voice, muscle development, genital growth, and facial and body hair. Testosterone is a type of androgen.