1610s, "to take in as food," from Latin ingestus, past participle of ingerere "to throw in, pour in, heap upon," from in- "into" (from PIE root *en "in") + gerere "to carry" (see gest). Related: Ingested; ingesting.
It is the hypothetical source of/evidence for its existence is provided by: Sanskrit antara- "interior;" Greek en "in," eis "into," endon "within;" Latin in "in, into," intro "inward," intra "inside, within;" Old Irish in, Welsh yn, Old Church Slavonic on-, Old English in "in, into," inne "within, inside."
"famous deed, exploit," more commonly "story of great deeds, tale of adventure," c. 1300, from Old French geste, jeste "action, exploit, romance, history" (of celebrated people or actions), from Medieval Latin gesta "actions, exploits, deeds, achievements," noun use of neuter plural of Latin gestus, past participle of gerere "to carry on, wage, perform," which de Vaan says is considered to be from the same root as agere "to set in motion, drive forward, do, perform" (from PIE root *ag- "to drive, draw out or forth, move"). Now only as a deliberate archaism. Jest (n.) is the same word, with a decayed sense.