Definition of isogloss in English:

isogloss

noun

Linguistics
  • A line on a dialect map marking the boundary between linguistic features.

    • ‘All words belonging to the same isogloss must have sound correspondences and clear similarities in form and meaning.’
    • ‘Although isoglosses are displayed as lines, they are actually transition areas where pronunciation gradually changes.’
    • ‘Such boundaries are called isoglosses and are themselves subjected to various shades of definition.’
    • ‘The following map, for example, shows several isoglosses for different grammatical features of Anishinaabemowin.’
    • ‘However, the conclusion maps used in the research are not synthetic but they are drawn up using isoglosses to present the findings.’

Origin

Early 20th century: from iso- equal + Greek glōssa tongue, word.

Pronunciation:

isogloss

/ˈīsəˌɡläs/