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A Greek measure of length, being the chief one used for itinerary distances, also adopted by the Romans for nautical and astronomical measurements. It was equal to 600 Greek or 625 Roman feet, or 125 Roman paces, or to 606 feet 9 inches English. This was also called the Olympic stadium, as being the exact length of the foot-race course at Olympia.

A kind of telemeter for measuring the distance of an object of known dimensions, by observing the angle it subtends; especially (Surveying), a graduated rod used to measure the distance of the place where it stands from an instrument having a telescope, by observing the number of the graduations of the rod that are seen between certain parallel wires (stadia wires) in the field of view of the telescope; -- also called stadia, and stadia rod.

In ancient Greece, the course for foot races, surrounded by tiers of seats for spectators; in modern times, a similar structure for athletic games, etc.

A certain period.

A Greek measure of 125 geometrical paces, or 625 Roman feet, equal to 606 feet 9 inches English; consequently the Greek stadium was somewhat less than our furlong; it was the principal Greek measure of length: the course for foot-races at Olympia in Greece, which was exactly a stadium in length; the name was also given to all other places throughout Greece wherever games were celebrated: in med. the stage or period of a disease, especially of an intermittent disease.

A stage in development or life-history of plant or animal.

Period, Stage.

L. for Stage.

pl., stadia. See stage (1st def.).