evocation (n.) Look up evocation at Dictionary.com
1570s, from Latin evocationem (nominative evocatio), noun of action from past participle stem of evocare "call out, rouse, summon," from ex- "out" (see ex-) + vocare "to call" (see voice (n.)).

Evocation was used of the Roman custom of petitioning the gods of an enemy city to abandon it and come to Rome; it also was used to translate the Platonic Greek anamnesis "a calling up of knowledge acquired in a previous state of existence."