Is it ensure, insure, or assure?
1540s, from Old French demolition (14c.) "demolition; defeat, rout," from Latin demolitionem (nominative demolitio), noun of action from past participle stem of demoliri (see demolish). Mencken noted demolition engineer for "house-wrecker" by 1936. Demolition derby is recorded from 1956, American English, defined by OED as "a contest in which old cars are battered into one another, the last one running being declared the winner."