Is it ensure, insure, or assure?
1630s, "a woman negligent or disordered in her dress or household," of uncertain origin, probably related to Low German Slattje, Dutch slodder, dialectal Swedish slata "slut" (in the older, non-sexual sense; cf. slut). Cf. dialectal English verb slatter "to spill or splash awkwardly, to waste," used of women or girls considered untidy or slovenly.