Plain-language clarity
Complex concepts like blood alcohol content (BAC) and respiratory rate are broken down without medical jargon overload.
Wellness is more than meals and workouts—it starts with knowing how your body works. Browse clear, NIH-sourced explanations for the vocabulary you hear at the doctor’s office and in everyday life.
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Short definitions backed by NIH and partner institutes—so you can read lab results, apps, and care instructions with confidence.
Complex concepts like blood alcohol content (BAC) and respiratory rate are broken down without medical jargon overload.
From blood type and Rh factor to body temperature and blood pressure readings—learn what the numbers mean for you.
Terms such as cervical mucus, ovulation tests, and basal body temperature help you interpret fertility and wellness data responsibly.
A sampling of definitions available on MedlinePlus—each with trusted institute attribution.
Force of blood on artery walls—systolic when the heart beats, diastolic between beats (e.g. 120/80).
Estimate of body fat from height and weight, useful for gauging weight-related health risks.
Types A, B, O, and AB plus Rh factor—how surface markers on blood cells are classified.
Alcohol concentration in blood, expressed for medical and legal reference.
Core vital signs that reflect cardiovascular and breathing status.
Resting morning temperature; subtle shifts may align with ovulation when tracked consistently.
Cycle-related changes that, with temperature, can help identify fertile windows.
Fundamental measures of heat regulation and growth tracking.
Practical terms for medication delivery, sun safety, menstruation, spotting, and daily wellness.
MedlinePlus is produced by the National Library of Medicine—a cornerstone of evidence-based public health education.
Open MedlinePlus and browse Definitions of Health Terms: General Health—the same resource clinicians and educators trust for accurate, readable explanations.
Open MedlinePlus definitions