late 14c., "petition (to God or a god) for aid or comfort; invocation, prayer;" also "a summoning of evil spirits," from Old French invocacion "appeal, invocation" (12c.), from Latin invocationem (nominative invocatio), noun of action from past participle stem of invocare "to call upon, invoke, appeal to" (see invoke).
Proto-Indo-European root meaning "to speak."
It forms all or part of: advocate; avocation; calliope; convocation; epic; equivocal; equivocation; evoke; invoke; provoke; revoke; univocal; vocabulary; vocal; vocation; vocative; vociferate; vociferous; voice; vouch; vox; vowel.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit vakti "speaks, says," vacas- "word;" Avestan vac- "speak, say;" Greek eipon (aorist) "spoke, said," epos "word;" Latin vocare "to call," vox "voice, sound, utterance, language, word;" Old Prussian wackis "cry;" German er-wähnen "to mention."
"to call; to name" (archaic), from Old English cleopian, clipian "to speak, call; summon, invoke; implore," which is of uncertain origin.
late 13c., "command on oath;" c. 1300, "summon by a sacred name, invoke by incantation or magic," from Old French conjurer "invoke, conjure" (12c.) and directly from Latin coniurare "to swear together; conspire," from assimilated form of com "with, together" (see con-) + iurare "to swear," from ius (genitive iuris) "law, an oath" (see jurist).
The magical sense is from the notion of "constraining by spell" a demon to do one's bidding. Related: Conjured; conjuring. Phrase conjure up "cause to appear in the mind" (as if by magic) attested from 1580s.
c. 1500, from French implorer and directly from Latin implorare "call on for help, beseech, beg earnestly," with a literal sense probably of "plead tearfully, invoke with weeping," from assimilated form of in- "on, upon" (from PIE root *en "in") + plorare "to weep, cry out," a word of unknown origin. Related: Implored; imploring; imploringly; imploration.
mid-15c., "a curse, cursing," from Latin imprecationem (nominative imprecatio) "an invoking of evil," noun of action from past participle stem of imprecari "invoke, pray, call down upon," from assimilated form of in- "into, in, within" (from PIE root *en "in") + precari "to pray, ask, beg, request" (from PIE root *prek- "to ask, entreat"). "Current limited sense is characteristic of human nature" [Weekley].
c. 1400, "to invoke spirits," from Old French exorciser (14c.), from Late Latin exorcizare, from Greek exorkizein "banish an evil spirit; bind by oath" (see exorcism). Sense of "call up evil spirits to drive them out" became dominant 16c. Formerly also exorcize; a rare case where -ise trumps -ize on both sides of the Atlantic, perhaps due to influence of exercise. Related: Exorcised; exorcising.