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ecphonesis

American  
[ek-fuh-nee-sis] / ˌɛk fəˈni sɪs /

noun

Rhetoric.
  1. the use of an exclamatory phrase, as in “O tempore! O mores!”


Etymology

Origin of ecphonesis

1580–90; < Greek ekphṓnēsis, equivalent to ekphonē-, variant stem of ekphōneîn to cry out ( ec-, -phone ) + -sis -sis