Pitch accent

Pitch accent is a feature of certain languages whose variations in pitch (linguistic tones) can be used to differentiate words, but the potentially distinctive tones are restricted to one or two syllables within a word. That contrasts with fully-tonal languages like Standard Chinese in which each syllable can have an independent tone. In a pitch accent language, the syllable with phonemic tone is typically acoustically prominent (stressed). Also, many words may not be marked for tone at all.

Languages that have been described as pitch accent languages include certain Scandinavian and South Slavic languages, Latvian and Lithuanian, Ancient Greek, Vedic Sanskrit, Japanese, Korean, Yaqui and Shanghainese.

It has been claimed that the term "pitch accent" is not coherently defined. Indeed, it is also used to denote a different feature, namely the use or relatively strong use of pitch, as opposed to other cues like acoustic intensity, to give prominence (accent) to a syllable or mora within a word. The latter feature is dealt with in the article pitch accent (intonation).

Pitch-accented languages may have a more complex accentual system than stress-accented languages. In some cases, they have more than a binary distinction but are less complex than fully tonal languages such as Chinese or Yoruba, which assign a separate tone to each syllable. For example, in Japanese short nouns (1-4 moras) may have a drop in pitch after any one mora but more frequently on none at all so in disyllabic words followed by a particle, there are three-way minimal contrasts such as kaꜜki wa "oyster" vs. kakiꜜ wa "fence" vs. kaki wa "persimmon". Ancient Greek words had high pitch on one of the last four vocalic morae in a word, and since a vowel may have one or two morae, a syllable can be accented in one of four ways (high pitch, rising pitch, falling pitch, none). Also, the mapping between phonemic and phonetic tone may be more involved than the simple one-to-one mapping between stress and dynamic intensity in stress-accented languages.

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