雙元音

關於拼字時兩個一組的元音字母，且通常不分別發成兩個元音的情況，請見「二合字母」。

American English pronunciation of no highway cowboys, showing five diphthongs: /oʊ aɪ eɪ aʊ ɔɪ/

雙元音（diphthong）是一種複元音（compound vowel），又稱雙元音或二合複元音，在語音學中，指聯合的兩個元音，它們作為一個整體出現。之間有平滑的過渡，也就是說，雙元音中的發音牽涉到兩種不同的舌位，並且從其中一種舌位滑動到另一舌位。在國際音標 (IPA) 中，單元音用一個字母表示，如[ʌ]。雙元音用兩個字母表示，如[aɪ]，響度較低的字母可以加上  ̯ 符號以表示它是雙元音的一部份，例如 [aɪ̯]。

雙元音的類型

雙元音依響度的變化可分為上升雙元音與下降雙元音（或稱上升複元音與下降複元音）。上升複元音以響度較低的元音開始，以響度較高的元音結束，例如 [ɪ̯a]。下降複元音以響度較高的元音開始，以響度較低的元音結束，例如 [aɪ̯]。在某些語言或研究中，會將下降複元音視為真正的雙元音，至於上升複元音則傾向於被當作相鄰出現的兩個元音。例如在漢語中，上升複元音常被當作介音與主要元音的結合，而下降複元音則被當作一個整體的押韻單位。

參見

• 音位變異
• 三元音

參考文獻

• Birbosa, Plínio A.; Albano, Eleonora C., Brazilian Portuguese, Journal of the International Phonetic Association, 2004, 34 (2): 227–232, doi:10.1017/S0025100304001756 
• Bertinetto, Pier Marco; Loporcaro, Michele, The sound pattern of Standard Italian, as compared with the varieties spoken in Florence, Milan and Rome, Journal of the International Phonetic Association, 2005, 35 (2): 131–151, doi:10.1017/S0025100305002148 
• Borg, Albert J.; Azzopardi-Alexander, Marie, Maltese, Routledge, 1997, ISBN 0-415-02243-6 
• Carbonell, Joan F.; Llisterri, Joaquim, Catalan, Journal of the International Phonetic Association, 1992, 22 (1-2): 53–56, doi:10.1017/S0025100300004618 
• Chițoran, Ioana, The Phonology of Romanian: A Constraint-based Approach, Berlin & New York: Mouton de Gruyter, 2001, ISBN 3-11-016766-2 
• Chițoran, Ioana, A perception-production study of Romanian diphthongs and glide-vowel sequences, Journal of the International Phonetic Association, 2002a, 32 (2): 203–222, doi:10.1017/S0025100302001044 
• Chițoran, Ioana, The phonology and morphology of Romanian diphthongization, Probus, 2002b, 14 (2): 205–246, doi:10.1515/prbs.2002.009 
• Cruz-Ferreira, Madalena, European Portuguese, Journal of the International Phonetic Association, 1995, 25 (2): 90–94, doi:10.1017/S0025100300005223 
• Faria, Arlo, Applied Phonetics: Portuguese Text-to-Speech, University of California, Berkeley, 2003, CiteSeerX: 10.1.1.134.8785 
• Gussenhoven, Carlos, Dutch, Journal of the International Phonetic Association, 1992, 22 (2): 45–47, doi:10.1017/S002510030000459X 
• Kaye, Jonathan; Lowenstamm, Jean, De la syllabicité, Dell, François; Vergnaud, Jean-Roger; Hirst, Daniel (編), La forme sonore du langage, Paris: Hermann: 123–159, 1984 [2016-10-22], （原始內容存檔於2014-01-07） 
• Kleine, Ane, Standard Yiddish, Journal of the International Phonetic Association, 2003, 33 (2): 261–265, doi:10.1017/S0025100303001385 
• Kohler, Klaus J., German, Handbook of the International Phonetic Association: A guide to the use of the International Phonetic Alphabet, Cambridge: Cambridge University Press: 86–89, 1999, ISBN 0-521-65236-7, doi:10.1017/S0025100300004874 
• Krech, Eva Maria; Stötzer, Ursula, Großes Wörterbuch der deutschen Aussprache, Leipzig: VEB Bibliographisches Institut, 1982, ISBN 978-3323001404 
• Martínez-Celdrán, Eugenio; Fernández-Planas, Ana Ma.; Carrera-Sabaté, Josefina, Castilian Spanish, Journal of the International Phonetic Association, 2003, 33 (2): 255–259, doi:10.1017/S0025100303001373 
• Mangold, Max. Das Aussprachewörterbuch 3rd. Dudenverlag. 1990. ISBN 3-411-20916-X （德語）. 
• Mascaró, Joan, Catalan Phonology and the Phonological Cycle (Doctoral thesis), Massachusetts Institute of Technology, 1976 [12 December 2013], （原始內容存檔於2014-01-07） 
• Meinhold, Gottfried; Stock, Eberhard, Phonologie der deutschen Gegenwartssprache, Lepzig: VEB Bibliographisches Institut, 1980 
• Peters, Jörg, The Flemish–Brabant dialect of Orsmaal–Gussenhoven, Journal of the International Phonetic Association, 2010, 40 (2): 239–246, doi:10.1017/S0025100310000083 
• Roach, Peter, British English: Received Pronunciation, Journal of the International Phonetic Association, 2004, 34 (2): 239–245, doi:10.1017/S0025100304001768 
• Padgett, Jaye, Glides, Vowels, and Features, Lingua, 2007, 118 (12): 1937–1955, doi:10.1016/j.lingua.2007.10.002 
• Schane, Sanford, Diphthongization in Particle Phonology, Goldsmith, John A. (編), The Handbook of Phonological Theory, Blackwell Handbooks in Linguistics, Blackwell: 586–608, 1995 
• Tingsabadh, M.R. Kalaya; Abramson, Arthur, Thai, Journal of the International Phonetic Association, 1993, 23 (1): 24–28, doi:10.1017/S0025100300004746 
• Tröster-Mutz, Stefan, Variation of vowel length in German (PDF), Groningen, 2011 [2016-10-22], （原始內容存檔 (PDF)於2016-03-04） 
• Verhoeven, Jo, Belgian Standard Dutch, Journal of the International Phonetic Association, 2005, 35 (2): 243–247 [12 December 2013], doi:10.1017/S0025100305002173, （原始內容存檔於2013-12-16） 
• Verhoeven, Jo, The Belgian Limburg dialect of Hamont, Journal of the International Phonetic Association, 2007, 37 (2): 219–225, doi:10.1017/S0025100307002940 
• Verhoeven, Jo; Van Bael, C., Akoestische kenmerken van de Nederlandse klinkers in drie Vlaamse regio’s, Taal en Tongval, 2002, 54: 1–23 
• Wiese, Richard, The Phonology of German, Oxford: Oxford University Press, 1996, ISBN 0-19-824040-6