Definition of proparoxytonous in US English:

proparoxytonous

adjective

Phonetics Linguistics
rare
  • = proparoxytonic.

Origin

Mid 18th century; earliest use found in Henry Gally (1696–1769), Church of England clergyman and writer. From post-classical Latin proparoxytonus or its etymon Hellenistic Greek προπαροξύτονος having an acute accent on the antepenultimate syllable + -ous.