A Judgment-Free Glossary of Sexual Health Terms

Sexual health has a lot of terms, and not everyone received the same education. Some of us got comprehensive sex ed. Some of us got fear, silence, and a diagram from 1974. Some of us learned everything from friends, clinics, the internet, or one very confident person who was only half right.

This glossary is here to help.

No shame. No quiz. No glitter-covered dunce cap.

STI

STI stands for sexually transmitted infection. It refers to infections that can spread through sexual contact, including oral, anal, vaginal, front-hole, genital, or skin-to-skin contact depending on the infection.

STD

STD stands for sexually transmitted disease. Many people now use STI instead of STD because infection can be present without symptoms or disease. You may still see both terms used by clinics, labs, and older resources.

HIV

HIV stands for human immunodeficiency virus. HIV affects the immune system. With proper treatment, people living with HIV can live long, healthy lives.

AIDS

AIDS stands for acquired immunodeficiency syndrome. AIDS is the most advanced stage of HIV. Not everyone with HIV has AIDS. HIV treatment can prevent HIV from progressing to AIDS.

PrEP

PrEP stands for pre-exposure prophylaxis. It is medicine taken before possible HIV exposure to help prevent HIV. CDC states that PrEP can reduce the risk of getting HIV from sex by about 99% when taken as prescribed.

PEP

PEP stands for post-exposure prophylaxis. It is emergency medicine that may help prevent HIV after a possible exposure. PEP must be started within 72 hours, and sooner is better. (cdc.gov)

U=U

U=U means Undetectable = Untransmittable. A person living with HIV who takes HIV medicine as prescribed and maintains an undetectable viral load has zero risk of sexually transmitting HIV to partners.

Viral Load

Viral load is the amount of HIV in a person’s blood. HIV treatment can lower viral load. When viral load is so low that standard tests cannot detect it, it is called undetectable.

Undetectable

Undetectable means HIV is controlled so well by treatment that standard lab tests cannot detect it in the blood. Undetectable does not mean cured, but it does mean HIV is controlled and, when maintained, is not sexually transmitted.

Serostatus

Serostatus usually refers to whether someone is HIV-positive or HIV-negative. You may hear someone say they know their status, disclose their status, or ask about a partner’s status.

Seroconversion

Seroconversion is the period when the body begins producing detectable antibodies after an infection, such as HIV. During this time, some tests may not yet detect the infection. This is one reason window periods matter.

Window Period

A window period is the time between a possible exposure and when a test can reliably detect an infection. Testing too soon can sometimes give a negative result even if an infection is developing. For HIV, different tests have different window periods.

Asymptomatic

Asymptomatic means having no symptoms. Many STIs can be asymptomatic, which means someone can have an infection and feel completely fine.

Barrier Method

A barrier method creates a physical layer between bodies, fluids, toys, or skin. Examples include external condoms, internal condoms, dental dams, gloves, and condoms used on sex toys.

External Condom

An external condom is worn over the penis or some sex toys. It can help reduce the risk of HIV, some STIs, and pregnancy when used correctly.

Internal Condom

An internal condom is worn inside the vagina, front hole, or anus. It can provide barrier protection and may give the receptive partner more control over condom use.

Dental Dam

A dental dam is a thin sheet used as a barrier during oral sex on the vulva, vagina, front hole, or anus.

DoxyPEP

DoxyPEP stands for doxycycline post-exposure prophylaxis. It is an antibiotic-based prevention strategy that some providers may discuss with certain people at increased risk for bacterial STIs. It is not for everyone and should be discussed with a healthcare provider. CDC issued clinical guidelines in 2024 recommending clinicians discuss doxy PEP with certain men who have sex with men and transgender women at increased risk for bacterial STIs.

HPV

HPV stands for human papillomavirus. It is very common. Some types can cause genital warts, and some can cause certain cancers. Vaccination can help prevent many HPV-related health problems.

Hepatitis

Hepatitis means inflammation of the liver. Hepatitis A, B, and C are different viruses. Hepatitis A and B can be prevented with vaccines. Hepatitis C does not currently have a vaccine, but testing and treatment are available.

Mpox

Mpox is a viral infection that can spread through close physical contact, including intimate or sexual contact. Vaccination may be recommended for people with certain risk factors or exposures, depending on public health guidance.

Consent

Consent means freely agreeing to what is happening. Consent should be ongoing, specific, informed, enthusiastic, and reversible.

Harm Reduction

Harm reduction means meeting people where they are and offering tools to reduce risk without shame. In sexual health, that can include condoms, PrEP, PEP, testing, vaccines, lube, communication, consent, and safer hookup planning.

Partner Notification

Partner notification means letting a current or recent sexual partner know they may need STI testing or treatment. This can be done directly, through a provider, through a health department, or sometimes through anonymous notification tools.

Reinfection

Reinfection means getting an infection again after treatment. This can happen if a partner was not treated, if someone is exposed again, or if prevention steps are not in place.

A Sisterly Blessing

You do not have to know every term to deserve care.

You are allowed to ask questions. You are allowed to learn late. You are allowed to say, “I do not know what that means.” The goal is not perfect vocabulary. The goal is informed, shame-free care.

May your questions be welcomed, your providers be clear, and your search history be blessed.