Diphthong

dif′thong, or dip′thong, n. two vowel-sounds pronounced as one syllable.— adj. Diphthong′al , relating to a diphthong.— adv. Diphthong′ally .— n. Diphthongā′tion .— v.t. Diph′thongise . [Through Fr. from Gr. diphthongos , with two sounds— di- , twice, phthongos , sound.]