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definitions

diphthongize

[ dif-thawng-ahyz, -gahyz, -thong-, dip- ]
/ ˈdɪf θɔŋˌaɪz, -ˌgaɪz, -θɒŋ-, ˈdɪp- /
Phonetics

verb (used with object), diph·thong·ized, diph·thong·iz·ing.

to change into or pronounce as a diphthong.

verb (used without object), diph·thong·ized, diph·thong·iz·ing.

to become a diphthong.

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Nearby words

diphtheritic, diphtheritic membrane, diphtheroid, diphthong, diphthongia, diphthongize, diphycercal, diphyletic, diphyllobothriasis, diphyllobothrium, diphyllous
Also especially British, diph·thong·ise.

Origin of diphthongize

First recorded in 1865–70; diphthong + -ize
Related formsdiph·thong·i·za·tion, noun
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

British Dictionary definitions for diphthongization

diphthongize

diphthongise

/ (ˈdɪfθɒŋˌaɪz, -ˌɡaɪz, ˈdɪp-) /

verb

(often passive) to make (a simple vowel) into a diphthong
Derived Formsdiphthongization or diphthongisation, noun
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012