Definition of obtestation in English:

obtestation

noun

rare
  • The action of calling God (heaven, etc.) to witness; protestation; an instance of this; an oath.

Origin

Mid 16th century (in an earlier sense). From Middle French, French † obtestation or its etymon classical Latin obtestātiōn-, obtestātiō the action of calling upon, solemn invocation, the action of beseeching or imploring, earnest entreaty from obtestāt-, past participial stem of obtestārī + -iō.

Pronunciation

obtestation

/ˌɒbtɛsˈteɪʃn/