levity

Webster's Dictionary (GCIDE)

1.The quality of weighing less than something else of equal bulk; relative lightness, especially as shown by rising through, or floating upon, a contiguous substance; buoyancy; -- opposed to gravity. [1913 Webster]

He gave the form of levity to that which ascended; to that which descended, the form of gravity.— Sir. W. Raleigh.[1913 Webster]

This bubble by reason of its comparative levity to the fluidity that incloses it, would ascend to the top.— Bentley.[1913 Webster]

2.Lack of gravity and earnestness in deportment or character; trifling gayety; frivolity; sportiveness; vanity. " A spirit of levity and libertinism." --Atterbury. [1913 Webster]

He never employed his omnipotence out of levity.— Calamy.[1913 Webster]

3.Lack of steadiness or constancy; disposition to change; fickleness; volatility. [1913 Webster]

The levity that is fatigued and disgusted with everything of which it is in possession.— Burke.

Syn: Inconstancy; thoughtlessness; unsteadiness; inconsideration; volatility; flightiness.

Usage: Levity, Volatility, Flightiness. All these words relate to outward conduct. Levity springs from a lightness of mind which produces a disregard of the proprieties of time and place.Volatility is a degree of levity which causes the thoughts to fly from one object to another, without resting on any for a moment. Flightiness is volatility carried to an extreme which often betrays its subject into gross impropriety or weakness. Levity of deportment, of conduct, of remark; volatility of temper, of spirits; flightiness of mind or disposition. [1913 Webster]