Sadism:
A paraphilia in which sexual arousal becomes dependent on sexual role play or fantasy that includes giving punishment, discipline, or humiliation.

Sadomasochism (S and M):
The consensual use of domination and/or pain for sexual stimulation in sex play. The “sadist” is the partner who dominates and inflicts pain. The “masochist” is the partner who is dominated and receives pain.

“Safe Sex”:
Ways in which people reduce the risk of getting sexually transmitted infections, including HIV.

Scabies:
A contagious skin disease caused by the skin mite. It is an sexually transmitted disease. The female mite burrows beneath the skin and digs a short tunnel parallel to the surface in which it lays its eggs. After about a month the itching becomes intense.

Scrotum:
The pouch of skin behind the penis that holds the testes.

Sex Characteristics:
Characteristics of the body that are caused by hormones, develop during puberty, and last through adult life. For girls, these include breast development and widened hips. For guys, they include facial hair development. Both genders develop pubic hair and underarm hair. See Puberty Chart for Girls. Puberty Stages for Guys.

Semen:
A thick fluid, containing a mixture of glandular secretions and sperm cells, that is discharged from the penis during ejaculation.

Seminal Fluid:
A fluid that nourishes and helps sperm to move. Seminal fluid is made in the seminal vesicles.

Seminal Vesicle:
One of two glands located behind the male bladder, which secrete a fluid that forms part of semen.

Sex Drive:
The natural urge and desire to have sex.

Sexism:
Bias against a certain gender.

Sexology:
The scientific study of sex and sexuality through many disciplines including, but not limited to, anthropology, biology, sociology, history, psychology, medicine, and law.

Sex Play:
Any voluntary sexual activity, with or without a partner.

Sex Therapy:
Treatment to resolve a sexual problem or dysfunction such as premature ejaculation, inability to have orgasm, or low level of sexual desire, etc.

Sexual Abuse:
Sexual activity that is harmful or not consensual.

Sexual Addiction:
The compulsive search for having very frequent sex.

Sexual Assault:
The use of force or coercion, physical or psychological, to make a person engage in sexual activity.

Sexual Aversion Disorder:
The fear of sexual contact.

Sexual Compulsion:
An obsession with having very frequent sex, often with many different sex partners.

Sexual Desire:
A strong physically arousing attraction.

Sexual Discomfort:
Feelings of sexual inhibition that are not considered dysfunctional.

Sexual Dysfunction:
A psychological or physical disorder of sexual function.

Sexual Harassment:
Unwanted sexual advances with suggestive gestures, language, or touching.

Sexual Identity:
Feelings about ones own sexual orientation, gender, gender role, and gender identity.

Sexual Intercourse
The erect penis of the male entering the vagina of the female.

Sexuality:
Referring to the interplay of physical, psychological, social, emotional, and spiritual makeup of an individual. It also encompasses gender, gender role, gender identity, sexual orientation, sexual preference, and social norms as they affect physical, emotional, and spiritual life.

Sexually Transmitted Infections (STIs):
Infections that are often or usually passed from one person to another during sexual contact. Also called STDs.

Sexual Norm:
A cultural norm regarding sex or sexuality.

Sexual Orientation:
The term used to describe the gender of the objects of our sexual desires. People who feel sexual desire for members of the other gender are heterosexual, or straight. People who feel sexual desire for people of the same gender are homosexual, or gay. Gay women are called lesbians. People who are attracted to both genders are bisexuals.

Sexual Repression:
The suppression of sexual activities, ideas, or identities that are perceived to be harmful or morally wrong.

Sexual Response Cycle:
The pattern of response to sexual stimulation. The five stages of the cycle are desire, excitement, plateau, orgasm, and resolution.

Sexual Seduction:
Legally, the encouragement of a younger or less mature person into an illegal sexual situation.

Sexual Stereotype:
An overly simplified judgment or bias regarding the sexuality of a person or group.

Shaft:
A part of the penis and clitoris.

Smegma:
The secretions of the sebaceous glands, especially the cheesy secretion, consisting primarily of dead skin cells found beneath the foreskin. If left unwashed, it can become an unpleasant-smelling substance.

Social Stigma:
Severe disapproval for behavior that is not within cultural norms.

Sodomy:
Anal intercourse. Or (dictionary version) – any intercourse held to be abnormal.

Speculum:
A plastic or metal instrument used to separate the walls of the vagina so a health care provider can examine the vagina and cervix. Usually used in order to take a pap smear.

Speculum Exam:
Physical examination of the cervix that is accomplished by using a speculum.

Sperm:
Mature male sex cell.

Spermatozoa:
The mature sperm cell (about 0.05 ml. long)

Spermatozoon :
The mature male sex cell containing 23 chromosomes.

Spermarche:
The time when sperm is first produced by the testes of a boy.

Spermatogenesis:
The process of producing sperm. Spermatogenesis occurs in the somniferous tubules of the testes.

Spermicides:
Chemicals used to immobilize sperm and kill sperm.

Spirochetes:
Bacterial organisms that cause syphilis. Many other bacteria are in the shape of the Spirochete, for example, Lyme Disease is caused by a Spirochete.

Squeeze Technique:
A method for postponing early ejaculation.

Statutory Rape:
Sexual intercourse between an adult and anyone who is below the age of consent, whether or not it is voluntary.

STD (Sexually Transmitted Disease):
A sexually transmitted infection that has developed symptoms.

Stereotype:
An overly simplified judgment or bias regarding a person or group.

Sterilization:
Surgical methods of birth control that are intended to be permanent. These are: blocking of the fallopian tubes for women or the vas deferens in men). Known as tubal ligation and vasectomy

Straight:
Slang for a heterosexual.

Syphilis:
A sexually transmitted disease caused by a specific bacterial spirochete.