Archiater (Gr. chief physician), a title which seems in the first place to have been purely honorary and not official. In the times of the Roman emperors Greek physicians were encouraged to come to Rome and enter the imperial service; and it was to one of these, Andromachus the elder, that the title archia-ter was first given by Nero. What was intended only as a personal compliment to Andromachus passed rapidly into an institution, and archiater became a designation of a class. The archiatri were divided into two classes, the city archiatri and the court archiatri. Later it came to be a civil requirement (under Antoninus Pius) that small cities should have five archiatri, large ones seven, and the largest ten. The archiatri were salaried officers, and were expected to treat the poor gratuitously. As perquisites, they charged the rich for practice, and also had certain stipends called anno-naria commoda. It was also considered a part of their duty to teach medical science, and to exercise a general supervision over the health of their medical dioceses and the practice of the inferior physicians. The archiatri were usually elected by the suffrages of physicians.

In Sweden and Denmark the order still exists.