Coorda
A coorda (pronounced co-orda_) is a boundary created by specific points in both time and space.
Importantly, a coorda composes an event when associated to the actual entities occuring within its range.
For example, we can say that the Fall of Saigon was an event that happened in the coorda of the local-time afternoon of the 30th of April, 1975, in the Independence Palace of the then-called city of Saigon, Vietnam.
A coorda must carry both time and space information in order to be called one.