||Sta"di*um (?), n.; pl.
Stadia (#). [L., a stadium (in sense 1), from Gr.
?.] 1. 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. Dr. W.
Smith.
2. Hence, a race course; especially, the Olympic
course for foot races.
3. 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.
Sta"di*um (?), n. A modern
structure, with its inclosure, resembling the ancient stadium, used
for athletic games, etc.