primarily denotes "one nourished or brought up with another" (sun, "with," trepho, "to rear"); it is rendered "foster-brother" in Acts 13:1 , RV. It has, however, been found in Hellenistic usage as a court term, signifying an intimate friend of a king (Deissmann), and this would seem to be the meaning regarding Manaen and Herod the Tetrarch.
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