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demarcative

American  
[dih-mahr-key-tiv, dee-mahr-key-] / dɪˈmɑr keɪ tɪv, ˈdi mɑrˌkeɪ- /
Also demarcational

adjective

Linguistics.
  1. (of a phonological feature) serving to indicate the beginning or end of each successive word in an utterance, as word-initial stress in Hungarian or penultimate stress in Polish.


Etymology

Origin of demarcative

First recorded in 1950–55; demarcate + -ive