MedicalVocabulary.org
Medical vocabulary with 16,436 clear, complete and reliable definitions.
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The most complete online medical dictionary: 16,436 terms covering anatomy, physiology, pathologies, diagnostic exams, pharmacology and every clinical specialty.
Designed for 3 kinds of users:
- Patients and family who want to understand a diagnosis, a medical report or instructions from a doctor.
- Students of medicine, nursing, physiotherapy and the health professions, dealing with technical terminology.
- Doctors, pharmacists and healthcare workers who need a quick and reliable reference.
Definitions are written in clear, accessible language while keeping the rigor required for professional use. Each term has a dedicated URL, instant autocomplete search, and can be shared on WhatsApp, Facebook, X and via email with one click.
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Disclaimer: the content is for informational and educational purposes only and does not replace medical advice. If you have doubts about your health, always consult a qualified professional. In case of emergency call your local emergency number (911 in the US, 112 in the EU).
Heterochromatin, facultative
Heterochromatin that need not always be heterochromatic but which has the faculty to return to the normal euchromatic state. The inactive X chromosome is made up of facultative heterochromatin. When a woman transmits that X to a son, it…
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Show more- Stepfather The husband of a woman who had a child by another man
- Aphasia, acquired epileptiform See Landau-Kleffner syndrome
- Tyrosine An amino acid, one of the 20 building blocks of protein. A nonessential amino acid, tyrosine is produced from…
- T-4 cell A type of T cell that has CD4 markers on its surface and participates in the immune response by recognizing…
- Favism A condition characterized by hemolytic anemia (breakup of red blood cells) after eating fava beans (Vicia…
- Barotrauma, otic See: Otic barotrauma
- Vitamin C An essential nutrient found mainly in fruits and vegetables. The body requires vitamin C to form and maintain…
- Polymyositis Polymyositis: A chronic inflammatory disease of muscle that begins when white blood cells, the immune cells…
- Active euthanasia The active acceleration of a 'good' death by use of drugs etc, whether by oneself or with the aid of a…
- Osteogenesis imperfecta type 2 An inherited connective tissue disorder with extremely severe bone fragility. This is the lethal form of…
- Visceral pericardium The inner layer of the pericardium, a conical sac of fibrous tissue that surrounds the heart and the roots of…
- Darwin, Charles English naturalist (1809-82), considered the father of evolution. Darwin voyaged aboard the Beagle to see the…