- diphthong (n.)
[diphthong 词源字典]
- late 15c., from Middle French diphthongue, from Late Latin diphthongus, from Greek diphthongos "having two sounds," from di- "double" (see di- (1)) + phthongos "sound, voice," related to phthengesthai "utter, speak loudly."[diphthong etymology, diphthong origin, 英语词源]