For the planet, see Planet Eladamri.
The Eladamri, also known as the Empire of Roads, was a Multi-Verse-spanning civilization, the collapse of which led to the Age of Darkness, and whose people built the Roads and may have made magic possible by artificially modifying D.N.A.
The term 'Ancient' is often used to describe the Eladamri, even within their own terminology. In relatively modern times (throughout the Ages of the Alliance), the Eladamri were often known simply as Ancients, a colloquium for the long-lost civilization. The proper name was not discovered until A.Y. 6899, and not formally published until several years later.
However, Eladamrian translations were often found to use the term 'Ancient'. It was eventually determined that the name 'Eladamri' sprang from the establishment of the capitol city on the planet of the same name:
Feeling that their work was complete, the ancient ones moved on from the Old Way, and put aside their weapons. A new capital was established, and with it, a new name: Eladamri.
Based on this inscription, Jason posited that they chose the name at the start of Classic Antiquity, and that the name 'Ancient' described everything before that era. Perhaps the term was meant to distance the 'new way' from the old war against the Iname.
The First Ones
Another, much less common term, is the 'First Ones', found in many cultures in and around the known worlds. It is often found among cultures specifically seeded by the Ancients, who refer to themselves as "The Second Ones" or similar. See Progenitors & Progenitor Civilization.