n. pl. sta·di·ums or sta·di·a (-dē-ə)
1. A large, usually open structure for sports events with tiered seating for spectators.
2. A course on which foot races were held in ancient Greece, usually semicircular and having tiers of seats for spectators.
3. An ancient Greek measure of distance, based on the length of such a course and equal to about 185 meters (607 feet).
4. Medicine A stage or period in the course of a disease.
5. Biology A stage in the development or life history of an organism.
[Middle English, unit of length, from Latin, from Greek stadion, perhaps alteration (influenced by stadios, firm) of spadion, racetrack, from spān, to pull.]
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