Is it ensure, insure, or assure?
"to wander with no fixed destination," 1530s (earliest sense was "to shoot arrows at a mark selected at pleasure or at random," late 15c.); possibly a Midlands dialectal variant of northern English and Scottish rave "to wander, stray," from Middle English raven, probably from Old Norse rafa "to wander, rove" (cf. rave (v.)). Influenced by rover, if not a back-formation from it. Related: Roved; roving.