10 letters · 15 points in Scrabble
noun a prayer asking God's help as part of a religious service
noun an incantation used in conjuring or summoning a devil
noun calling up a spirit or devil
originFrom Middle English invocacioun, from Old French invocacion, from Latin invocatio, invocationem. Equivalent to invoke + -ation.
Etymology from Wiktionary, CC BY-SA 3.0