Prince, a Greek rhetorician, in whose “school” at Ephesus Paul disputed daily for the space of two years with those who came to him (Acts 19:9). Some have supposed that he was a Jew, and that his “school” was a private synagogue.
Easton’s Bible Dictionary
Tyrannus
Name meaninga prince; one that reigns
Easton’s Bible Dictionary (1897), public domain. Text via Theographic Bible Metadata, CC BY-SA 4.0.