sidon

Obligatory Contour Principle Usually abbreviated to OCP. A phonological principle which disallows adjacent identical tones in the lexical representation of a morpheme. See Kenstowicz (1994) for further detail
Obstruent [ˈɒbstrʊənt] A consonant articulation where there is a constriction close enough to cause an increase in air pressure in the vocal tract with respect to ambient air pressure. Plosives, fricatives and affricates are all members of the obstruent class. The opposite of obstruent is sonorant.
Occlusion [əˈkluːʒn] A closure in the vocal tract.
Occlusive [əˈkluːsɪv] An obsolete term for stop.
OCP abbreviation for Obligatory Contour Principle
Octave [ˈɒktɪv] The musical interval between two tones which are related by the doubling of the fundamental frequency. For example, two tones of 100Hz and 200Hz are an octave apart, as are two tones of 150Hz and 300Hz.
Oesophageal voice [iˌsɒfəˈdʒɪəl] The quasi-periodic vibration of the entrance to the oesophagus sometimes used by laryngectomised speakers to simulate vocal fold vibration.
Onset (1) The first pre-nuclear accented syllable in an intonation pattern. The stretch of the intonation pattern from the onset to (but not including the nucleus) is known as the head (2) A component of the syllable, consisting of any consonants which precede the syllable nucleus. The onset may be empty in some (but not all) languages. In the monosyllabic English word split the onset is the cluster of consonants [spl].
Open quotient The proportion of the vibratory cycle of the vocal folds for which the folds are not in contact.
Open syllable A syllable with an empty coda.
Open vowel See height
Opposition Another term for contrast
Optimality theory [ˌɒptɪˈmæləti] A phonological theory which views the differences between languages as the result of different rankings of universal constraints on phonological structure. See Prince and Smolensky.
Oral airstream mechanism The same as velaric airstream mechanism. See airstream mechanism.
Oral cavity The mouth cavity which contains the teeth, tongue, alveolar ridge, hard palate, soft palate and uvula. The forward boundary of the oral cavity is the lips and the rear boundary is the uvula.
Oral stop See stop.
Orbicularis oris muscle [ɔːˌbɪkjəˈlɑːrɪs ˈɔːrɪs] The major muscle controlling the position of the lips. Its contraction is necessary both for lip closure in bilabial sounds and for lip rounding in rounded vowels and consonants.
Organ of Corti See basilar membrane.
Oropharynx [ˌɔːrəʊˈfærɪŋks] The part of the pharyngeal cavity with lies behind the oral cavity.
Orthography [ɔːˈθɒɡrəfi] (adj.orthographic [ˌɔːθəˈɡræfɪk) The normal spelling system of a language.
Ossicles [ˈɒsɪklz] The small bones of the middle ear: hammer, anvil and stirrup.
Overlapping distribution See distribution
Oxytone [ˈɒksitəʊn] A word with lexical stress on the final syllable (e.g.balloon).