JTR Views 6 meanings found JTR is the airport code for Santorini, Greece, and commonly abbreviates Jack the Ripper, the U.S. military’s Joint Travel Regulations, and occasionally the blues musician John the Revelator. Miscellaneous Jaguars That Run John The Reverend Community John The Revelator, musician Governmental Joint Travel Regulations Jack The Ripper Regional Santorini, Thira Island, Greece