Medical Dictionary: Glossary (V)

What is vaccines?

Microbial preparations of killed or modified microorganisms that can stimulate an immune response in the body to prevent future infection with similar microorganisms.

What is vagus nerve?

An important nerve that supplies nerve fibers to the pharynx (throat), larynx (voice box), trachea (windpipe), lungs, heart, esophagus, and intestinal tract, as far as the transverse portion of the colon.

What is ventilation?

The exchange of air between the lungs and the atmosphere so that oxygen can be exchanged for carbon dioxide inside the alveoli (the tiny air sacs in the lungs).

What is vernix?

A white, cheesy substance that covers and protects the skin of a fetus. Vernix is still all over the skin of a baby at birth.

What is virus?

A small infectious agent that replicates only inside the living cells of other organisms. Viruses can infect all types of life forms, from animals and plants to microorganisms.

What is viremia?

The presence of a virus in the blood. Viremia is analogous to bacteremia (the presence of bacteria in the blood) and parasitemia (the presence of a parasite in the blood).

What is vocal cord?

One of two small bands of muscle within the larynx. These muscles vibrate to produce the voice.
The vocal cords form a “V” inside the larynx.

What is vitiligo?

A condition in which the skin turns white due to the loss of pigment from the melanocytes, cells that produce the pigment melanin that gives the skin color.

What is viscera?

The internal organs of the body, specifically those within the chest (as the heart or lungs) or abdomen (as the liver, pancreas or intestines).