(n.) The quality or state of being rectilinear.

Atticism appropriateness artlessness austerity baldness bareness bluffness bluntness broadness brusqueness candidness candor chasteness chastity childlikeness clarity classicalism classicism clear-cutness clearness coherence comeliness common speech connectedness consistency correctness crystallinity definition dignity discrimination distinction distinctness ease elegance elegancy explicitness felicitousness felicity finish fittingness flatness flow flowing periods fluency forthrightness frankness freedom freeness genuineness good taste grace gracefulness gracility guilelessness homespun horizontalness household words inartificiality ingenuousness innocence leanness limpidity lineality linearity lucidity matter-of-factness naiveness naivete naivety naturalness neatness openheartedness openness outspokenness pellucidity perspicuity plain English plain dealing plain speaking plain speech plain style plain words plainness plainspokenness polish propriety prosaicness prosiness purity rectilinearity refinement restrainedness restraint roundness rustic style seemliness severity simpleheartedness simplemindedness simpleness simplicity sincerity single-heartedness single-mindedness singleness of heart smoothness soberness spareness starkness straightforwardness straightness structure taste tastefulness terseness transparency transpicuity trustfulness unadorned style unadornedness unaffectedness unambiguousness unassumingness unconstraint unequivocalness unguardedness unimaginativeness unmistakableness unpoeticalness unpretentiousness unreserve unrestraint unsophisticatedness unsophistication unsuspiciousness unswervingness unwariness vernacular verticalness