From Latin īnsurgentem, accusative singular of īnsurgēns, present active participle of īnsurgō (“to rise up against, revolt”), from in (“against”) + surgō (“to rise”), itself from sub (“up from below”) + regō (“to guide, direct, rule, govern, administer”), from Proto-Indo-European *h₃reǵ- (“to move in a straight line, to rule, guide, lead straight, put right”).