isophone

isophone

(ˈaɪsəˌfəʊn)
n
(Linguistics) linguistics an isogloss marking off an area in which a particular feature of pronunciation is found
[C20: from iso- (as in isogloss) + -phone (as in phoneme)]
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References in periodicals archive ?
As mentioned (3.4.), Kristensson (1987: 212) considers /o/ before nasals to be the defining feature of the dialect of the West Midlands, stating that "it was the most conspicuous feature of the West Midlands (and still is), and it seems warranted to take the /o/ isophone as the boundary for the West Midland dialect area".
Yep, called the Isophone, the helmet contraption floats in a pool and, once you've popped your bonce inside, all other senses dwindle to a minimum.
A-weighted noise levels greatly underestimate loud low frequency noise because, at higher sound pressure levels, the isophones are much less frequency dependent than that at 20 phone that is reflected by the A-filter [16].
Road traffic noise was modeled according to Directive 2002/49/EC of the European Parliament and Council of the European Union (2002) for the year 2006 as a weighted day-evening-night (24-hr) average sound level ([L.sub.den]) in 5-A-weighted decibel [dB(A)] categories (isophones).
One should bear in mind, however, that the Estonian dialect division, which was established in its modern form by Andrus Saareste (1932), takes into account mostly the spread of phonetic and grammatical phenomena or isophones and isomorphs.
1982b "Isophones or isographs: A problem in historical dialectology", in: John Anderson (ed.) Language form and linguistic variation.