A prisoner, group of prisoners (heretofore known as a gang) or confederacy thereby having been known to be so tough in their sanctions against unaffiliated or hostile members per se that others remark upon the ponderance of their visage, that they indeed "Run the Yard".

In layman's parlance, this person or persons are so tough that they control a territory many believe indefensible and do so day after day, an example of a place indefensible being the aforementioned prison yard, a locale often thought of as having no intrinsic law and with little chance of the uplifting and common practice thereof.

In common talk, a person or persons that are tough and command the respect of opposing groups to the point those groups cede territory to the dominant person or persons.
Dorroile, upon his arrival at the keep, was alarmed to learn that atramentous men run the yard, for Dorroile was of an inimical progeny.
by Gene Creemers December 16, 2015
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when a female with gigantic tits takes her bra off before going to bed, her boobs move all over her body: up to her neck, down to her stomach, all over.
before pam went to bed she announced to all the girls at the sleep-over, that it was time to "Let the dogs run all over the yard"
by Meggiek November 12, 2007
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