instinct

From Latin īnstīnctus, the past participle of īnstinguō, meaning "to incite, to instigate." That verb itself comes from in- ("in, on") plus stinguō ("to prick").

The facts given don't trace a further shift in meaning beyond this Latin root — the word arrived already carrying the sense of something driven or goaded into action.

It shares its root stinguō, "to prick," with instiguō, the verb behind English "instigate" — both describe something being jabbed or spurred into motion.