Stress (phonology)

In linguistics, stress is the relative emphasis that may be given to certain syllables in a word. The term is also used for similar patterns of phonetic prominence inside syllables. The word accent is sometimes also used with this sense.The ways stress manifests itself in the speech stream are highly language dependent. In some languages, stressed syllables have a higher or lower pitch than non-stressed syllables — so-called pitch accent (or musical accent). In other languages, they may bear either higher or lower pitch than surrounding syllables (a pitch excursion), depending on the sentence type. There are also dynamic accent (loudness), qualitative accent (full vowels), and quantitative accent (length, known in music theory as agogic accent). Stress may be characterized by more than one of these characteristics. Further, stress may be realized to varying degrees on different words in a sentence; sometimes the difference between the acoustic signals of stressed and unstressed syllables may be minimal.
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