conjuration (n.) Look up conjuration at Dictionary.com
late 14c., coniuracioun, "conspiracy" (now obsolete), also "a calling upon something supernatural," from Old French conjuracion "spell, incantation, formula used in exorcism," from Latin coniurationem (nominative coniuratio) "a swearing together, conspiracy," noun of action from coniurare "to swear together; conspire," from com- "together" (see com-) + iurare "to swear" (see jury (n.)).