obsecration

ob`se`cra´tion

    (ǒb`sė`krā´shŭn)
n.1.The act of obsecrating or imploring; as, the obsecrations of the Litany, being those clauses beginning with "By."
2.(Rhet.) A figure of speech in which the orator implores the assistance of God or man.
Webster's Revised Unabridged Dictionary, published 1913 by G. & C. Merriam Co.