The word "Tretys" is a variation of the word "Triteis" which is what the ancient Greeks called the constellation of Orion. The spelling of "Tretys" may seem unusual, but it follows the phonetic transcription of the Greek word. In IPA, the pronunciation of "Triteis" is /triteis/. The "t" and "r" sounds are pronounced separately, followed by the "ay" sound in "ei". The "s" at the end is pronounced with a soft "uh" sound. Thus, "Tretys" can be pronounced as /tretuhs/.