Health Glossary

Demystifying medical language. Browse or search for clear, human-centered explanations of common medical terms.

Global Warming

Global warming is the long-term increase in Earth’s average surface temperature, primarily caused by human activities that increase the concentration…
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Gynecology

The branch of medicine concerned with the health, diseases, and disorders of the female reproductive system and related aspects of…
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Hazard

The inherent potential of a substance, organism, activity, or situation to cause harm. Hazard describes what can cause harm, rather…
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Heatstroke

Heatstroke is a life-threatening medical emergency in which the body becomes dangerously overheated and its ability to regulate temperature fails,…
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Hepatitis

Inflammation of the liver. Hepatitis can have many causes, including viral infections, alcohol, certain medicines or toxins, autoimmune disease, and…
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Herd Immunity

Indirect protection from an infectious disease that occurs when a sufficiently large proportion of a population is immune, making transmission…
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HIV

Human immunodeficiency virus (HIV) is a retrovirus that attacks cells of the immune system and, without effective treatment, can progressively…
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Homeostasis

Homeostasis is the process by which the body maintains relatively stable internal conditions despite changes inside or outside the body.…
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Hormone

A chemical messenger produced by cells or tissues that travels through body fluids or acts locally to regulate the activity…
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Hygiene

Practices and conditions that help maintain health and reduce exposure to infectious agents and other harmful substances. Hygiene includes practices…
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Hypertension

A chronic medical condition in which blood pressure remains persistently elevated above the level considered appropriate for health. Hypertension develops…
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Immune Cell

A cell that contributes to the body’s immune defense by recognizing, responding to, or helping control infectious agents, abnormal cells,…
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