Bible Dictionaries
Patmos

Holman Bible Dictionary

(pat' muhss) A small island (ten miles by six miles) in the Aegean Sea located about thirty-seven miles southwest of Miletus. The Romans used such places for political exiles. John's mention of the island in Revelation 1:9 probably means that he was such a prisoner, having been sent there for preaching the gospel. Eusebius (an early church father) wrote that John was sent to Patmos by Emperor Domitian in A.D. 95 and released after 1 1/2 years. See Revelation.

Bibliography Information
Butler, Trent C. Editor. Entry for 'Patmos'. Holman Bible Dictionary. https://www.studylight.org/​dictionaries/​eng/​hbd/​p/patmos.html. 1991.