Is it ensure, insure, or assure?
Old English wrecca "wretch, stranger, exile," from Proto-Germanic *wrakjan (cf. Old Saxon wrekkio, Old High German reckeo "a banished person, exile," German recke "renowned warrior, hero"), related to Old English wreccan "to drive out, punish" (see wreak). Sense of "vile, despicable person" developed in Old English, reflecting the sorry state of the outcast, as presented in much of Anglo-Saxon verse (e.g. "The Wanderer"). Cf. German Elend "misery," from Old High German elilenti "sojourn in a foreign land, exile."