adj. Lacking worldly experience and understanding, especially:adj. Simple and guileless; artless: a child with a naive charm. adj. Unsuspecting or credulous: "Students, often bright but naive, bet—and lose—substantial sums of money on sporting events” ( Tim Layden). adj. Showing or characterized by a lack of sophistication and critical judgment: "this extravagance of metaphors, with its naive bombast” ( H.L. Mencken). adj. Not previously subjected to experiments: testing naive mice. adj. Not having previously taken or received a particular drug: persons naive to marijuana. n. One who is artless, credulous, or uncritical.