This sexual health glossary gives clear, evidence-informed definitions for anatomical terms, STI testing terms, contraception terms and sexual-medicine concepts — in straightforward adult language, without clinical jargon. Each entry carries a phonetic pronunciation so you can say it out loud at an appointment.
A persistent or recurrent difficulty, delay, or inability to achieve orgasm following normal sexual arousal and adequate stimulation.
Can be primary (lifelong) or secondary (acquired due to stress, medications like SSRIs, hormonal shifts, or neurological conditions). Treatable with therapy, medication adjustment, and pelvic floor work.
Presenting no outward symptoms or signs of disease, even when an infection is active and transmissible.
The majority of STIs—including chlamydia, gonorrhoea, HPV, and early HIV—are asymptomatic in most individuals, which is why routine exposure-based testing is essential.
A common vaginal condition caused by an imbalance in the natural vaginal microbiome, specifically an overgrowth of anaerobic bacteria over protective Lactobacillus species.
Often causes thin grayish discharge and a noticeable 'fishy' odor, especially after sex or washing. Treated with prescription antibiotics (metronidazole or clindamycin); not classified as an STI.
Two small pea-sized glands located slightly below and to the left and right of the vaginal opening.
They secrete small amounts of fluid that help lubricate the vulval vestibule and labia minora during arousal. Can occasionally develop cysts or infections if ducts become blocked.
The lower, narrow part of the uterus that connects the uterine cavity to the upper vagina.
Produces cervical mucus that changes texture across the menstrual cycle. Routinely screened via cervical smear / Pap / HPV tests to prevent cervical cancer.
A very common sexually transmitted bacterial infection that can infect the cervix, urethra, rectum, and throat.
Usually asymptomatic. If untreated, can lead to Pelvic Inflammatory Disease (PID), chronic pelvic pain, or epididymitis. Diagnosed via urine test or swab and treated with antibiotics.
The two internal 'legs' or roots of the clitoris that extend backward and downward along the pubic arch.
Composed of erectile tissue that engorges with blood during arousal, hugging the vaginal wall and contributing significantly to internal pleasure during stimulation.
A complex, highly sensitive erectile organ dedicated exclusively to sexual pleasure, containing over 10,000 sensory nerve endings in the glans alone and extending internally around the vagina.
Consists of the glans, hood (prepuce), shaft (body), vestibular bulbs, and crura. Engorges with blood during sexual arousal.
Methods containing both synthetic oestrogen and progestogen (pills, patches, vaginal rings) that suppress ovulation and thicken cervical mucus.
Highly effective (>99% perfect, 91% typical). Contraindicated for people with high cardiovascular risks, migraine with focal aura, or hypertension.
An informed, voluntary, specific, uncoerced, and ongoing agreement to participate in a particular sexual act.
Can be revoked at any time. Requires capacity (not incapacitated by alcohol, drugs, or sleep) and cannot be assumed from silence, past encounters, or clothing.
A non-hormonal intrauterine device wrapped in copper wire that prevents fertilisation and implantation by releasing copper ions.
Effective for 5 to 10 years (>99% efficacy) and functions as the most reliable method of emergency contraception if inserted within 5 days of unprotected sex.
A thin sheet of latex or polyurethane placed over the vulva or anus during oral sex (cunnilingus or anilingus) to block the transmission of bodily fluids and skin pathogens.
Reduces transmission of HPV, herpes, gonorrhoea, and syphilis during oral sex.
Persistent or recurrent pain occurring before, during, or after sexual intercourse or penetration.
Can be superficial (at the entrance) or deep (in the pelvis). Potential causes include infections, endometriosis, lack of lubrication, hormonal changes, and pelvic floor hypertension.
Interventions used after unprotected sex, condom failure, or missed birth control pills to prevent unintended pregnancy.
Includes oral pills (Levonorgestrel within 72h, Ulipristal acetate within 120h) and the Copper IUD (within 120h). Does not terminate established pregnancies.
A tightly coiled, curved duct located behind each testicle where newly produced sperm mature and are stored prior to ejaculation.
Can become inflamed (epididymitis) due to bacterial infections such as chlamydia or urinary tract infections, causing testicular swelling and pain.
The consistent or recurring inability to achieve or maintain an erection firm enough for satisfactory sexual activity.
Common and treatable. Caused by vascular, hormonal, neurological, or psychological factors (stress, performance anxiety). Often treated with PDE5 inhibitors (e.g. sildenafil, tadalafil), lifestyle changes, or psychosexual therapy.
A common viral infection caused by the Herpes Simplex Virus that can cause recurring clusters of small, tender blisters or sores in the genital, anal, or oral areas.
Many people have no symptoms. Spread through skin-to-skin contact, even when no sores are visible (asymptomatic viral shedding). Managed effectively with antiviral medications (acyclovir, valacyclovir).
A bacterial STI caused by Neisseria gonorrhoeae that infects the mucous membranes of the genitals, rectum, and throat.
Can cause painful urination and yellow/green discharge, but is frequently asymptomatic in women and throat infections. Treated with targeted antibiotic injections and tablets.
A virus that attacks the body's immune system, specifically CD4 T cells. If untreated, can progress to AIDS.
Effectively prevented with condoms and PrEP/PEP, and effectively managed with modern antiretroviral therapy (ART) so people with undetectable viral loads cannot transmit the virus (U=U: Undetectable = Untransmittable).
A large family of over 200 related viruses spread through skin-to-skin intimate contact.
High-risk strains (e.g. HPV 16 and 18) are associated with cervical, anal, and throat cancers; low-risk strains (e.g. HPV 6 and 11) cause genital warts. Preventable with the HPV vaccine (Gardasil 9).
A thin, flexible fold of mucous membrane tissue that partially surrounds the external opening of the vagina.
It does not 'seal' the vagina. It naturally stretches, thins, and wears with age, tampon use, exercise, and sexual activity. Bleeding during first-time sex is not a biological requirement and often relates to friction or lack of arousal.
A small T-shaped device inserted into the uterus by a healthcare provider for long-acting, reversible contraception.
Available as non-hormonal copper IUDs (5-10 years) or hormonal progestogen-releasing IUS devices (3-8 years). Over 99% effective.
An individual's overall sexual drive, interest, or desire for sexual activity.
Naturally fluctuates across life stages due to stress, fatigue, relationship dynamics, medications, hormones, and mental health. No single frequency is medically 'correct'.
A substance applied to genitalia, toys, or barriers to reduce friction, enhance comfort, prevent tissue tears, and heighten pleasure.
Water-based (versatile and toy/condom compatible), silicone-based (long-lasting and condom compatible), and oil-based (safe for solo use, but damages latex condoms).
The transition (perimenopause) and point in time (menopause) marking the cessation of menstrual cycles and significant decline in oestrogen and progesterone.
Can cause vaginal dryness, thinning of vulvovaginal tissues (Genitourinary Syndrome of Menopause / GSM), and changes in desire. Treatable with vaginal oestrogen, systemic HRT, and moisturisers.
A molecular laboratory test that detects the genetic material (DNA or RNA) of pathogens like Chlamydia, Gonorrhoea, and Trichomonas.
Highly sensitive and specific; performed using first-catch urine samples or swabs from the vagina, cervix, rectum, or throat.
A sudden release of accumulated sexual tension characterized by rhythmic muscular contractions in the pelvic floor and intense physical pleasure.
Driven by oxytocin, dopamine, and endorphin release. Orgasmic response varies widely by type of stimulation, mood, and physiological factors.
A hammock-like sling of muscles spanning the bottom of the pelvis, supporting the bladder, bowel, and uterus or prostate.
Critical for bladder control, erectile rigidity, vaginal support, and orgasmic contractions. Can be hypertonic (overly tight, causing pain) or hypotonic (weak).
A 28-day course of emergency antiretroviral medications taken after a potential high-risk exposure to HIV to prevent the virus from establishing infection.
Must be started within 72 hours of exposure (the sooner, the better). Available at hospital emergency departments and sexual health clinics.
Medication taken regularly (daily or event-driven) by HIV-negative individuals before potential exposures to reduce the risk of acquiring HIV by over 99%.
Common brand names include Truvada and Descovy. Requires regular HIV and kidney function monitoring every 3 months. Does not protect against other STIs.
A prolonged, painful erection that lasts for 4 hours or longer, unrelated to sexual stimulation or persisting after ejaculation.
A critical medical emergency. Blood becomes trapped in the erectile chambers of the penis and can cause permanent tissue necrosis if not treated urgently in an ER.
A walnut-sized gland in the male reproductive system located just below the bladder and surrounding the urethra.
Produces seminal fluid that nourishes and transports sperm. Highly sensitive to pressure and touch (sometimes referred to as the male G-spot).
The recovery phase following orgasm during which an individual is temporarily physiologically incapable of achieving another erection or orgasm.
Varies from minutes to hours or days depending on age, arousal levels, and individual neurochemistry.
A set of practical strategies—including barrier methods, testing, vaccines, and medications—designed to minimize the transmission of STIs and unintended pregnancy.
The term 'safer sex' is preferred over 'safe sex' because no single method completely eliminates all physiological risk.
A bacterial infection spread through direct contact with a syphilis sore (chancre) during vaginal, anal, or oral sex.
Progresses in stages: Primary (painless ulcer), Secondary (rash, flu symptoms), Latent, and Tertiary (organ damage). Diagnosed via blood antibody testing and easily cured with penicillin injections.
A medical emergency occurring when a testicle rotates, twisting the spermatic cord that brings blood to the scrotum.
Causes sudden, severe scrotal pain and swelling. Requires emergency surgery within 6 hours to restore blood flow and save the testicle.
A very common sexually transmitted infection caused by a microscopic protozoan parasite (Trichomonas vaginalis).
Can cause frothy greenish-yellow vaginal discharge, vulval irritation, or penile burning, but often causes no symptoms. Treated with oral metronidazole.
A medically proven consensus that people living with HIV on antiretroviral therapy (ART) who maintain an undetectable viral load cannot transmit HIV sexually to their partners.
Endorsed by the WHO, CDC, and UNAIDS based on landmark trials (PARTNER, Opposites Attract).
An involuntary, reflexive tightening or spasm of the pelvic floor muscles around the vaginal opening when penetration is attempted.
Makes inserting a tampon, receiving a pelvic exam, or vaginal intercourse painful or impossible. Highly treatable with pelvic floor physical therapy, vaginal dilators, and cognitive behavioral therapy.
The smooth, sensitive area of tissue enclosed by the labia minora that contains the urethral opening and vaginal entrance.
Rich in nerve endings and mucous glands (Bartholin's and Skene's). Can become hypersensitive in conditions like vulvodynia or vestibulodynia.
The complete external female genitalia, distinct from the internal vagina.
Includes the mons pubis, labia majora (outer lips), labia minora (inner lips), clitoral hood and glans, urethral opening, and vaginal vestibule.
The time between potential exposure to an infection and the point at which a diagnostic test can reliably detect the pathogen, its antigens, or the body's antibodies.
Varies by infection: e.g. Chlamydia/Gonorrhoea NAAT (1-2 weeks), 4th-generation HIV blood test (45 days), Syphilis blood test (3-6 weeks).
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