Is it ensure, insure, or assure?
1580s, "the whole world, cosmos," from Old French univers (12c.), from Latin universum "the universe," noun use of neuter of adj. universus "all together," literally "turned into one," from unus "one" (see one) + versus, past participle of vertere "to turn" (see versus). Properly a loan-translation of Greek to holon "the universe," noun use of neuter of adj. holos "whole" (see safe (adj.)).