Is it ensure, insure, or assure?
"to be subjected to or exposed to, to endure without complaint," now Scottish and Northern English dialect, from Old English þolian, from Proto-Germanic stem *thul- (cf. Old Saxon tholon, Old High German dolon, German geduld, Old Norse þola, Gothic þulan), cognate with Latin tolerare (see toleration).
"peg," from Old English þoll, from Proto-Germanic *thulnaz (cf. Old Norse þollr, Middle Low German dolle, East Frisian dolle, Dutch dol), of unknown origin. No record of the word in English from c.1000 to mid-15c.