Petechia

Part of speech: noun

Definitions

1. A small red or purple spot on the skin caused by bleeding beneath the surface
2. Tiny lesions on the body’s exterior that result from minor bleeding or capillary rupture
3. Small, flat, round spots on the skin indicative of a hemorrhage from tiny blood vessels

Etymology: Doctors in the sixteenth and seventeenth centuries used Italian clinicians' term "petecchie" for the tiny skin eruptions that appear in some fevers, and the English word "petechia" came from that Italian plural, passed through New Latin. Its roots run back to the Latin "impetigo," a word for a skin eruption or scab, which was shortened in popular speech to a diminutive form. The Italian word preserves the plural ending, a reminder that the spots were first named in groups rather than one at a time. Since the Latin ancestor is the same one behind "impetigo," the two medical terms are close relatives, though they describe different conditions. "Impetigo" names a contagious infection that produces crusted sores, while "petechia" refers to a flat spot formed when tiny blood vessels leak beneath the skin. The shared origin sits in the older sense of a skin eruption, and the medical vocabulary later sorted the two conditions apart.