diphthongizePronunciation: /ˈdɪfθɒŋʌɪz, ˈdɪp-/ (also diphthongise)Definition of diphthongize verb [with object] change (a vowel) into a diphthong: the short vowel was not lengthened or diphthongizedDerivatives diphthongizationPronunciation: /-ˈzeɪʃ(ə)n/ noun diphthongize in other Oxford dictionaries Definition of diphthongize in the US English dictionary
