Glossary
adolescent growth spurt: rapid increase in the individual’s height and weight during puberty resulting from simultaneous release of growth hormones, thyroid hormones, and androgens. Males experience their growth spurt about two years later, on average, than females
adrenarche: an increase in the production of androgens by the adrenal cortex that usually occurs during the eighth or ninth year of life and typically peaks at around 10 to 14 years of age and is eventually involved in the development of pubic hair, body odor, skin oiliness, and acne
anorexia nervosa: an eating disorder characterized by self-starvation. Affected individuals voluntarily undereat and often overexercise, depriving their vital organs of nutrition. Anorexia can be fatal
binge-eating disorder: an eating disorder characterized by recurrent episodes of eating large quantities of food (often very quickly and to the point of discomfort); a feeling of a loss of control during the binge; experiencing shame, distress or guilt afterward; and not regularly using unhealthy compensatory measures (e.g., purging) to counter the binge eating. It is the most common eating disorder in the United States
body dissatisfaction: negative subjective evaluation of the weight and shape of one’s own body, which may predict the onset, severity, and treatment outcomes of eating disorders
body image: a person’s idea of how his or her body looks
bulimia nervosa: an eating disorder characterized by binge eating and subsequent purging, usually by induced vomiting and/or use of laxatives
estrogen: primary female sex hormone that is responsible for the development and regulation of the female reproductive system and secondary sex characteristics
gonad: a sex organ that produces gametes; specifically, a testicle or ovary
gonadarche: refers to the earliest gonadal changes of puberty. In response to pituitary gonadotropins, the ovaries in girls and the testes in boys begin to grow and increase the production of the sex steroids, especially estradiol and testosterone
masturbation: sexual self-stimulation, usually achieved by touching, stroking, or massaging the male or female genitals until this triggers an orgasm
menarche: a girl’s first menstrual period, signaling that she has begun ovulation. Pregnancy is biologically possible, but ovulation and menstruation are often irregular for years after menarche
muscle dysmorphia: sometimes called “reverse anorexia” this is an obsession with being small and underdeveloped; extreme concern with becoming more muscular
primary sex characteristics: the parts of the body that are directly involved in reproduction, including the vagina, uterus, ovaries, testicles, and penis
puberty: the period of rapid growth and sexual development that begins in adolescence
secondary sex characteristics: physical traits that are not directly involved in reproduction but that indicate sexual maturity, such as a man’s beard or a woman’s breasts
sexually transmitted infections (STIs): diseases that are spread by sexual contact, including syphilis, gonorrhea, genital herpes, chlamydia, and HIV/AIDS
spermarche: a boy’s first ejaculation of sperm. Erections can occur as early as infancy, but ejaculation signals sperm production. Spermarche may occur during sleep (nocturnal emission or “wet dream”) or via direct stimulation
testosterone: the primary male sex hormone that plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristics such as increased muscle and bone mass, and the growth of body hair. Females also produce testosterone, but at a lower level than males