(n.) The quality or state of being thin (in any of the senses of the word).

Lenten fare admission of light airiness airy nothing airy texture attenuation austerity bodilessness chinchiness chintziness clarity clearness crystal-clearness crystallinity deadness delicacy diaphaneity diaphanousness dilutedness dilution ethereality exiguity exiguousness exility fewness filminess fineness flatness flavorlessness flightiness flimsiness fluffiness frailty frivolousness frothiness gauziness glassiness glasslikeness gossameriness gracility immateriality inanity incorporeality infrequency insipidity insipidness insolidity insubstantiality jejuneness jejunity laciness lack of depth leanness lifelessness lightness limpidity lucidity meagerness meanness mildness miserliness mistiness narrowness nonopacity paltriness paperiness parsimony paucity pellucidity puniness rareness rarity restrictedness saplessness savorlessness scantiness scantness scarcity scrawniness scrimpiness shallow-wittedness shallowness sheerness show-through skimpiness slenderness slightness slim pickings slimness smallness spareness sparseness sparsity staleness stinginess stringency subtility subtilty subtlety superficiality tastelessness tenuity tenuousness tightness transmission of light transparence transparency transpicuousness uncloudedness unprofoundness unprofundity unsavoriness unsubstantiality vagueness vapidity vitreosity vitreousness vitrescence volatility wateriness weakness wishy-washiness wispiness