U

ultrasound

High-frequency sound waves that can be bounced off tissue within the body as echoes and converted to a picture called a sonogram.

ultraviolet (UV) radiation

Solar energy in wavelengths of 290 to 400 nanometers (nm) that can have both beneficial and detrimental effects to human health. For example, UV radiation induces the production of vitamin D in the skin. However, overexposure to UV radiation can result in premature skin aging (due to a breakdown in collagen), sunburn, and skin cancers, including melanoma. To protect against these detrimental effects, lifeguards and others who find themselves exposed to the sun should use a broad-spectrum sunscreen, wear appropriate clothing including a hat with a brim, and use sunglasses with broad-spectrum UV protection.

umbilical cord

The cord that connects the growing fetus to the placenta and through which runs the umbilical arteries and veins. The umbilical cord is clamped and cut after birth and the residual tip becomes the umbilicus (belly button).

umbilicus

The belly button.

unassisted childbirth

The birth of a baby without the assistance of an obstetrician, midwife, or other health care professional.

unconsciousness

A condition of complete or near-complete unresponsiveness to people and environmental stimuli. Especially when caused by an injury or sudden illness, this should be considered a life-threatening emergency.

underwater swimming

Any kind of swimming below the surface of the water, usually involving sweeping arm strokes and a whip or scissors kick. Prolonged underwater swimming and breath holding, especially when preceded by hyperventilation, is a dangerous practice that can lead to shallow water blackouts and drowning.

underventilation

The state in which reduced amount of air enters the alveoli of the lungs, resulting in a decreased amount of oxygen in the blood stream. Also known as hypoventilation.

undulate

To rise and fall like a wave.

unicellular

Consisting of one cell only.

United States Aquatic Sports (USAS)

The organization that acts as the United States member federation in FINA (the Federation Internationale de Natation), representing United States Masters Swimming, United States Synchronized Swimming, USA Diving, USA Swimming, and USA Water Polo. According to FINA rules, each country must have only one recognized member federation of FINA.

United States Coast Guard (USCG)

A maritime, military, multimission branch of the United States Armed Forces with authority to provide maritime law enforcement in domestic and international waters and to act as a federal regulatory agency over maritime matters. As part of its mission, the USCG provides boating safety classes and approves and classifies all life jackets and personal flotation devices.

United States Coast Guard Auxiliary

Under the direction of the United States Coast Guard, the USCG Auxiliary ensures homeland security and recreational boating safety by conducting security patrols, search and rescue missions, disaster relief, pollution response, commercial fishing exams, recreational boating safety classes, and any mission assigned by the Commandant of the US Coast Guard or the Secretary of Homeland Security.

United States Masters Swimming (USMS)

The national organization with responsibility for, and authority over, the masters swimming program in the United States. Age groups for masters swimming are organized as follows: 18-24, 25-29, 30-34, 35-39, 40-44, 45-49, 50-54, 55=59, 60-64, 65-69, 70-74, 75-79, 80-84, 85-89, 90-94, and 95 and over.

United States Paralympics

As a division of the U.S. Olympic Committee, the organization responsible for underwriting the expenses of U.S. teams in the Parapan American and Paralympic Games.

United States Pharmacopeia (USP)

A publication, established in 1820, that contains legally recognized standards of identity, strength, quality, purity, packaging/labeling of drug substances.

United States Power Squadrons (USPS)

A nonprofit, educational organization, established in 1914, dedicated to making boating safer and more enjoyable by teaching boating safety and navigation courses to the general public.

United States Public Health Service (USPHS)

The agency responsible for the public health of the American people. The USPHS admionisters such critical health agencies as the Food and Drug Administration (FDA), the Centers for Disease Control (CDC), and the National Institutes of Health (NIH).

United States Sailing

The national governing body for the sport of sailing.

United States Synchronized Swimming (USSS)

The national governing body for synchronized swimming in the United States.

United States Water Fitness Association (USWFA)

A nonprofit organization committed to excellence in water fitness education. The USWFA offers the following national certifications: Primary Water Fitness Instructor, Master Water Fitness Instructor, Aquatic Fitness Personal Trainer, Masters Aquatic Fitness, Water Walking Instructor, Aquatic Director, and Aquatic Fitness Coordinator.

universal donor

An individual with type O blood (in the ABO blood typing system) who can donor blood to all recipients.

unresolved grief

Deep sadness or despair characterized by an extended duration; by intensity of feelings, thoughts, and actions; and/or by the interference of normal functioning.

unstable diabetes

A type of diabetes in which the person’s blood glucose level often quickly swings from high to low and from low to high. Also called brittle diabetes.

unsteadiness

Loss of equilibrium with regard to the environment.

urethra

The transport tube leading from the bladder to discharge urine outside the body.

urine

Transparent, amber-colored liquid waste excreted from the body by way of the bladder and urethra.

USA Diving

The national governing body for diving in the United States, organized into three programs: Junior Olympic, Senior, and Masters.

USA Swimming

The national governing body for amateur competitive swimming in the United States, organized on three levels: international, national, and local. In addition, USA Swimming has the following classifications for competition: Senior (all registered swimmers); Junior (all registered swimmers 18 and under); Age Group/Junior Olympic (all registered swimmers groups by ages 10 and under, 11-12, 13-14, 15-16, and 17-18); Post Age Group (all registered swimmers over 18 included in age group programs); Masters (all swimmers 18 years and older registered with United States Masters Swimming); and Long Distance (all registered swimmers).

USA Triathlon

The national governing body for the multisport disciplines of aquathlon, duathlon, triathlon, and winter triathlon in the United States. USA Triathlon is a member federation of theU.S. Olympic Committee and the International Triathlon Union.

USA Water Polo (USWP)

The national governing body for water polo in the United States.

USAS

United States Aquatic Sports.

USCG

United States Coast Guard.

USMS

United States Masters Swimming.

USP

United States Pharmacopeia.

USPHS

United States Public Health Services.

USPS

1. United States Power Squadrons. 2. United States Postal Service.

USSS

United States Synchronized Swimming, Inc.

USWFA

United States Water Fitness Association.

USWP

USA Water Polo, Inc.

uteris

The hollow, pear-shaped organ in a woman’s lower abdomen between the bladder and the rectum. During pregnancy, the uteris receives the fertilized egg and holds the growing fetus until full term when it contracts to deliver the baby and the placenta. A common name for the uteris is the womb.

UV

Ultraviolet.

V

V-Fib

Ventricular fibrillation.

V-Tach

Ventricular tachycardia.

vaccination

The injection of a weakened or killed microbe in order to stimulate the immune system against the microbe, thereby preventing disease.

vagina

The muscular canal that extends from the cervix (at the base of the uteris) to the outside of the body.

vascular

Of or relating to the blood vessels of the body.

vector

A carrier of an infectious agent, capable of transmitting the infection to another organism. Examples of vectors include mosquitos, fleas, ticks, mammals with rabies, etc.

vector-borne illness

A disease transmitted by a carrier. For example, mosquitos can transmit malaria and other diseases.

vein

A blood vessel that carries blood of low oxygen content from the cells of the body to the heart.

velvet ant

A solitary, wingless female wasp that greatly resembles a large, colorful, furry ant. The velvet ant can deliver a painful sting.

venereal disease

One of the various diseases transmitted during sexual activity by direct contact or by the transfer of infected semen, vaginal fluid, and/or blood. Venereal diseases include AIDS, chlamydia, genital herpes, genital warts, gonorrhea, hepatitis B and C, syphilis, and yeast infections. These diseases are also referred to as sexually transmitted diseases (STDs).

venin

Another name for snake venom.

venom

Poison secreted or injected by an animal or insect.

ventilation

The exchange of air between the lungs and the atmosphere. Alveolar ventilation refers to the exchange of gases in the alveoli.

ventricle

One of the connected cavities of the central brain or one of the lower chambers of the heart.

ventricular fibrillation (V-Fib)

An abnormal, irregular heart rhythm characterized by the uncoordinated fluttering of the lower chambers (ventricles) of the heart that disrupts the pulse and normal blood flow.

ventricular tachycardia (V-Tach)

An abnormal heart rhythm originating in one of the ventricles and characterized by excessively rapid contractions that may not effectively pump blood. Ventricular tachycardia can lead to ventricular fibrillation.

vermin

Any of the various small animals or insects, such as rats or cockroaches, that are annoying, destructive, or injurious to health.

vertebra

One of the 33 bone segments in the human spinal column, consisting of 7 cervical, 12 thoracic, 5 lumbar, 5 sacral (fused into 1 sacrum bone), and 4 coccygeal (fused into 1 coccyx bone) vertebrae.

vertebrae

The preferred plural of vertebra. The alternate plural of vertebra is vertebras.

vertex

The top of the head.

vertex presentation

The crowning of the baby’s head when delivery is imminent.

vertical

In anatomy, upright.

vertigo

A feeling of dizziness in which everything appears to be spinning. Vertigo is medically different than simple dizziness, lightheadedness, or unsteadiness.

vesicle

A small blister.

vessel

1. In anatomy, a tube-like structure through which fluids pass, such as a blood vessel or a lymph vessel. 2. In water safety, a craft for traveling on water, such as a boat or a ship.

victim

A drowning, distressed, ill, or injured person who must be rescued before he or she can be cared for. A victim becomes a patient when the rescuer begins to administer first aid care.

victim recognition

An objective of lifeguard surveillance accomplished by identifying the behaviors of active and passive drowning victims as well as ill, injured, or distressed victims.

violence

The exertion of physical force so as to injure or abuse.

violence-free discipline

A system of behavior training that does not include corporeal punishment. This system can involve the following strategies: natural consequences, logical consequences, withholding privileges, and time outs.

violin spider

Another name for the various recluse spiders (genus Loxosceles), notably the brown recluse, due to the violin pattern on the dorsal side of their cephalothorax.

viral

Of or relating to a virus.

Virginia Graeme Baker Pool and Spa Safety Act

United States Federal legislation enacted in 2007 to encourage states to institute swimming pool safety laws designed to prevent suction entrapment due to faulty pool and spa drains.

virus

A microorganism smaller than bacteria, which cannot grow or reproduce apart from a living cell. Viruses invade living cells and use the cell’s chemical machinery to keep themselves alive and replicate.

vision

1. The sense by which the qualities of an object (e.g., color, luminosity, size, shape, etc.) constituting its appearance are perceived through a process in which light rays reflected from the object entering the eye are transformed by the retina into electrical signals that are transmitted to the brain by the optic nerve. 2. The act or power of seeing.

vision impairment

Partial or total loss of sight.

visual acuity

The clarity of one’s vision.

visual field

The entire area that can be seen when looking forward, including that which is seen with peripheral vision.

vocal cords

The thin, reedlike folds of mucous membranes in the larynx, consisting of an upper pair (false vocal cords) and a lower pair (true vocal cords). The lower pair of vocal cords can rotate to partially obstruct the air passage and then vibrate when air is forced through them to produce sound waves called voice.

voice box

The portion of the respiratory tract that contains the vocal cords. The medical term for voice box is larynx.

void

To urinate.

voluntary

Of or relating to the somatic nervous system that controls muscles according to the conscious will of the individual.

vomit

Stomach content ejecting through the m.outh.

vomiter

One who vomits.

vomiting

The forcible voluntary or involuntary emptying of the stomach contents through the mouth.