Donatus, a Latin grammarian and rhetorician of the 4th century, the teacher of St. Jerome; the author of treatises in grammar known as Donats, and, along with the sacred Scriptures, the earliest examples of printing by means of letters cut on wooden blocks, and so appreciated as elementary treatises that they gave name to treatises of the kind on any subject; he wrote also scholia to the plays of Terence.
Definition taken from The Nuttall Encyclopædia, edited by the Reverend James Wood (1907)
Donatists * Donau