Concept
The phonology of Portuguese varies among dialects, in extreme cases leading to some difficulties in intelligibility. Portuguese is a pluricentric language and has some of the most diverse sound variations in any language. This article on phonology focuses on the pronunciations that are generally regarded as standard. Since Portuguese is a pluricentric language—and differences between European Portuguese (EP), Brazilian Portuguese (BP), and Angolan Portuguese (AP) can be considerable—varieties are distinguished whenever necessary. The consonant inventory of Portuguese is fairly conservative. The medieval Galician-Portuguese system of seven sibilants (/ts dz/, /ʃ ʒ/, /tʃ/, and apicoalveolar /s̺ z̺/) is still distinguished in spelling (intervocalic c/ç z, x g/j, ch, ss -s- respectively), but is reduced to the four fricatives /s z ʃ ʒ/ by the merger of /tʃ/ into /ʃ/ and apicoalveolar /s̺ z̺/ into either /s z/ or /ʃ ʒ/ (depending on dialect and syllable position), except in parts of northern Portugal (most notably in the Trás-os-Montes region). These changes are known as deaffrication. Other than this, there have been no other significant changes to the consonant phonemes since Old Portuguese. However, several consonant phonemes have special allophones at syllable boundaries (often varying quite significantly between European and Brazilian Portuguese), and a few also undergo allophonic changes at word boundaries. Phonetic notes Semivowels contrast with unstressed high vowels in verbal conjugation, as in (eu) rio /ˈʁi.u/ 'I laugh' and (ele) riu /ˈʁiw/ 'he (has) laughed.' Phonologists debate whether their nature is vowel or consonant. In intervocalic position semivowels are ambisyllabic, they are associated to both the previous syllable and the following syllable onset. In Brazil and Angola, the consonant hereafter denoted as /ɲ/ is realized as a nasal palatal approximant ȷ̃, which nasalizes the vowel that precedes it: ninho ([ˈnij̃u ~ ˈnjij̃u ~ ˈɲij̃u] in Brazil, [ˈnĩj̃u] in Angola) 'nest'.