The ⚀quadqua·lengthel, or ⚀stadial·length
The fourth dozenal power of the ⚀lengthel, the ⚀quadqua·lengthel (abbreviated ⚀q↑lgℓ) is one dozen ⚀habital·lengths, or one gross ⚀ell·lengths, or one galore ⚀hand·lengths, or one dozen galore ⚀morsel·lengths. This is the distance traversed in one ⚀breather (10d|ᘔz minutes) when moving at one ⚀velocitel. In SI units, this comes out to exactly 170.0784d meters. In USC units, this is exactly 558d|3ᘔ6z feet, or 186d|136z yards.
The nearest modern-day analog to this length that comes to mind is the furlong. However, at 660d|470z feet, the furlong is a rather poor match: It comes out to about 1.22z ⚀quadqua·lengthels, more than a sixth too large; the ⚀quadqua·lengthel is only about 84.5%d|ᘔ1.9%z of a furlong, almost a sixth too small.
However, there is an ancient unit of measure that makes a rather better match: the Greek stadion (στάδιον), Latinized as stadium, and Anglicized as stade. Herodotus defined the stadion as being 600d|420z feet. However, different ancient Greek city-states had different definitions of the foot. Two prominent ones were the standard Attic/Alexandrian foot of about 308d milimeters, which would place the stadion at about 185d meters; and the Olympic foot (from the city-state of Olympia) of about 294d milimeters, which would place the stadion at about 176d meters. The ⚀quadqua·lengthel comes to about 91.9%d|Ɛ0.5%z of the Attic stadion, and to about 96.6%d|Ɛ7.2%z of the Olympic stadion. On the strength of this correspondence, Primel will adapt the Latin form of this word, to make the ⚀stadial·length the colloquialization for the ⚀quadqua·lengthel. It still makes a good approximation for the size of most modern sports stadiums.