isophone

noun

linguistics an isogloss marking off an area in which a particular feature of pronunciation is found

Word Origin for isophone

C20: from iso- (as in isogloss) + -phone (as in phoneme)
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012