Definition of assassinatress in English:

assassinatress

noun

rare
  • A female assassin.

Origin

Mid 19th century; earliest use found in ‘Ouida’ (1839–1908), novelist (real name Marie Louise de la Ramée). From assassinator + -ess: see -tress.

Pronunciation

assassinatress

/əˈsasɪneɪtrɪs/