From Latin 'evocare' (to call out) — originally a Roman military term for summoning veterans out of retirement.
To bring or recall a feeling, memory, or image to the conscious mind; to call forth or summon.
From Latin ēvocāre (to call out, to summon, to call forth from a place or state), from ē- / ex- (out, from) + vocāre (to call, to name, to summon), from vox, vocis (voice). Latin vox descends from PIE *wekw- (to speak, voice, utterance), the same root behind Sanskrit vak (speech, divine word), Greek ēpos (word, story), and Old English wōp (sound, wailing). To evoke something is literally to call it out of wherever it resides — a memory, a spirit
In the Roman army, 'ēvocātī' were veteran soldiers who had completed their service but were 'called out' of retirement by a general for a new campaign. These recalled veterans were among the most experienced and dangerous troops on the battlefield — Julius Caesar relied heavily on his evocati during the civil wars.