adj. 25B6; adjective
their jejune opinions : NAIVE, innocent, artless, guileless, unworldly, childlike, ingenuous, unsophisticated; credulous, gullible; childish, immature, juvenile, puerile, infantile.
the following poem is rather jejune : BORING, dull, tedious, dreary; uninteresting, unexciting, uninspiring, unimaginative; humdrum, run-of-the-mill, mundane, commonplace; lacklustre, dry, sterile, lifeless, vapid, flat, bland, banal, trite, prosaic; Brit. informal samey; N. Amer. informal ornery.
sophisticated, fascinating.