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.
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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).
Mega- (prefix)
The combining form 'mega-' comes from the Greek 'megas', great or big and means abnormally large. Megalocephaly is too large a head. Megacardia is too large a heart. Megacolon is too large a colon.
Read the definitionRandom terms
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- Rad Radiation absorbed dose, a measure for a dose of ionizing radiation
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- Ab ovo Latin expression for 'from the beginning.' Ab ovo literally means 'from the egg.
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