Is it ensure, insure, or assure?
mid-14c., "action of correcting," from Old French correccion (13c.) "correction, amendment; punishment, rebuke," from Latin correctionem (nominative correctio), noun of action from past participle stem of corrigere (see correct (v.)). Meaning "chastisement" is from late 14c. Meaning "an instance of correction" is from 1520s. House of correction was in a royal statute from 1575.