Health Glossary

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

Pimple

A pimple is a common nontechnical term for a small, visible acne lesion or similar skin bump. People commonly use…
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Placenta

The placenta is a temporary organ that develops within the uterus during pregnancy and connects the pregnant woman’s circulation with…
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Plasmodium

Plasmodium is a genus of parasitic, single-celled organisms that includes the parasites responsible for malaria in humans and other animals.…
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Plasticizer

A substance added to a polymer or other materials to increase flexibility, workability, durability, or other physical properties. Plasticizers are…
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Platelet

A platelet (thrombocyte) is a tiny cell fragment that helps stop bleeding by forming blood clots. Platelets are produced in…
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Pneumonia

An infection or inflammatory condition affecting lung tissue, particularly the parts of the lungs involved in gas exchange. Pneumonia can…
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Polymer

A polymer is a substance made of large molecules composed of many repeating chemical units linked together into long chains…
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Pregnancy

Pregnancy is the period during which a baby develops inside the uterus, beginning after implantation and ending with childbirth. It…
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Printing Ink

Printing ink is a formulation containing pigments, dyes, binders, solvents, additives, or other components used to create printed images, text,…
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Prognosis

The expected course, outcome, or future health effects of a disease or medical condition. A prognosis is an informed estimate…
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Prokaryote

An organism whose cells lack a membrane-bound nucleus and other membrane-bound organelles characteristic of eukaryotic cells. Prokaryotes include bacteria and…
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