How to pronounce rein? This video provides examples of American English pronunciations of rein by male and female speakers. In addition, it explains the meaning of rein through a definition and several visual examples. IPA Transcription of rein is /rˈeɪn/. Definition of rein: Reins are the straps that hold a horse's head and neck. If you'd like to test your pronunciation of rein, check out Accent Hero's real-time pronunciation feedback tool: https://accenthero.com/app/pronunciat... or our Android app: https://play.google.com/store/apps/de...