lacking in sophistication or worldliness; "a child's innocent stare"; "his ingenuous explanation that he would not have burned the church if he had not thought the bishop was in it"世慣れしていない、または世俗的ではない純真
例:his ingenuous explanation that he would not have burned the church if he had not thought the bishop was in it 司教がその中にいると考えなかったならば、彼が教会を燃やさなかったという彼の率直な説明