sonority (n.)

A term in AUDITORY PHONETICS for the overall LOUDNESS of a sound relative to others of the same PITCH, STRESS and DURATION. Sounds are said to have an ‘inherent sonority’, which accounts for the impression of a sound’s ‘carrying further’, e.g. [s] carries further than , [a] further than [i]. Sonority is typically calculated along a scale from VOICELESS STOPS (least) to LOW VOWELS (most): voiceless stops – voiced stops – voiceless FRICATIVES – voiced fricatives – NASALS – LIQUIDS – GLIDES – high vowels – mid vowels – low vowels. LENITION processes increase a segments’s sonority and FORTITION processes decrease it.

In PHONOLOGY, a term used in attempts to define the SYLLABIC STRUCTURE of UTTERANCES. For example, the notion is important in AUTOSEGMENTAL (and specifically METRICAL) PHONOLOGY. In a sonority scale, or sonority hierarchy, the most sonorous elements are assigned the highest value, and the least sonorous the lowest value. The centre of a syllable (the syllabic NUCLEUS) is defined as the place where sonority is greatest (the sonority peak). Patterns of sonority sequence have been noted, leading to such observations as the sonority sequencing generalization: in any syllable, there is a SEGMENT constituting a sonority peak which is preceded and/or followed by a sequence of segments with progressively decreasing sonority values. In OPTIMALITY THEORY, the term refers to a CONSTRAINT which requires that syllable ONSETS increase in sonority and CODAS decrease in sonority.

The notion of visual sonority is used in the phonological analysis of the various features of SIGN language.