jejune /d͡ʒəˈdʒuːn/ adjective3 •Lacking matter; empty; devoid of substance. •Naive; simplistic.This renders the recognition of alternatives a paramount necessity for a logic of discovery, which can no longer dismiss them with a jejune chapter on 'disjunctive propositions'. — 1917 •(no longer used, old-fashioned) Not nutritious. formsmore jejune · most jejune