Epidemic
Etymology
From Greek "epidemos" (among the people, prevalent), from "epi-" (upon) and "demos" (the people). Literally something that falls upon the population — the "demos" root also lives in "democracy" and "demographic."
noun · /ep-ih-DEM-ik/
A sudden rise in cases of a disease above the normal level in a community.
What it names
Use it for an outbreak that spikes beyond what’s expected in one region or population, before it goes global.
Example
What began as a local epidemic in one city spread across borders within weeks.
Related idea
The scale ladder runs: endemic (steadily present in an area, like seasonal colds), epidemic (a sharp local surge above normal), and pandemic (an epidemic spread across countries or continents). The line between them is about geography and baseline, not severity.