Greek term (edited): Όσιος e.g. Όσιος Δαβίδ

HOLY PEOPLE (Latin "Saints"): Greek has two words for "Saint"—'áyios [older 'agios] and (for a monastic holy person) 'osios (sometimes mistranslated as "Blessed," a term used among the Latins for a person who is recognized as having the potential of being recognized as a Saint). We speak of "Holy Gregory" or "Holy Great Athansios." As "St. Vasil the Great" is not likely to disappear, so it will have to be tolerated. Christ's full title is "Lord, God, and Savior." The person called "John the Baptist" in the West is the Orthodox St. John the Forerunner, or more fully, "St. John, the holy glorious Prophet, Forerunner (Pródromos), and Baptizer." The author of the fourth Gospel is St. John the Theologian ["Divine" in the West] or in some calendars fully, St. John the Apostle and Evangelist" (the last word referring to the authorship of one of the fourth Gospel). There are three other Saints with the title "Theologian," viz. St. Gregory (of Nazianzós) the Theologian, St. Symeon the New Theologian, and St. Gregory (Palamãs) the Theologian. The names Matthew, Isaiah, and Elijah end in -ias in Greek: Matthias, Esaias, and Ilias. Cf. Zacharias (Zachary in the West).
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Also in Greek dictionaries.

Όσιος Δαβίδ was a hermit on Euboea (16th c.).