R0037300 (răng′kər)n. Bitter, long-lasting resentment; deep-seated ill will: He was filled with rancor after losing his job.[Middle English, from Old French, from Late Latin, rancid smell, from Latin rancēre, to stink, be rotten.]ran′cor·ous adj.ran′cor·ous·ly adv.ran′cor·ous·ness n. ThesaurusSeerancor