In linguistics, synaeresis or syneresis (see American and British spelling differences) is a sound change (metaplasm) by which two vowels are pronounced together rather than separately. The opposite is diaeresis.
Synaeresis comes from Greek (syna resis) "a taking" or "drawing together", from (synair ) "with" and "grasp".
In Ancient Greek, synaeresis is the pronunciation of two separate vowels as a diphthong ( ), and diaeresis is the separation of a diphthong into two vowels ( ).
Certain words in Proto-Indo-European had two vowels separated by the consonant s or y (esu "good"). In Greek, this consonant changed to h (ehu), and was lost between vowels (eu). In Homer, the two vowels were sometimes pronounced separately (diaeresis: ) and sometimes together (synaeresis: ). Later in Attic Greek, they were always pronounced together.
In Modern Greek, where original diphthongs are pronounced as monophthongs, synaeresis is the pronunciation of two vowel sounds as a monophthong ( , and diaeresis is the pronunciation of the two vowels as a diphthong ( ).
Synaeresis often occurs with English reduced vowels, as in Asia ( ).
br:Sinairezenn de:Kontraktion (Linguistik) es:Sin resis (m trica) fr:Syn r se gl:Sin rese nl:Syneresis (taalkunde) pl:Synereza (j zykoznawstwo) pt:Sin rese ru: