(n.) Quality or state of being volatile; disposition to evaporate; changeableness; fickleness.

airiness animation ascent brainlessness bubbliness buoyancy caducity changeability changeableness coquettishness corruptibility daintiness death delicacy downiness empty-headedness ephemerality ephemeralness ethereality evanescence evaporability faddishness faddism fickleness finitude fleetingness flightiness flippancy floatability fluffiness foaminess foolishness frivolity frivolousness frothiness fugacity gentleness giddiness gossameriness impermanence impermanency inconstancy instability lack of depth lack of weight levitation levity lightness mercuriality mercurialness momentariness mortality mutability perishability shallow-wittedness shallowness skittishness softness sprightliness superficiality tenderness thinness thoughtlessness transience transiency transientness transitoriness undependability unheaviness unpredictability unprofoundness unprofundity unreliability vaporability vaporizability variability weightlessness witlessness yeastiness