1851, from Fr. impasse "impassable road, blind alley, impasse," from in- "not" + M.Fr. passe "a passing," from passer "to pass." Supposedly coined by Voltaire as a euphemism for cul de sac.
Main Entry: im·passe Pronunciation: 'im-"pas, im-'pas Function: noun : a point in esp. labor negotiations at which reaching an agreement is impossible because neither party is willing to compromise or change position