Emily Dickinson Lexicon

LEV'I-TY, n. [L. levitas, from levis, light; connected perhaps with Eng. lift.]

1. Lightness; the want of weight in a body, compared with another that is heavier. The ascent of a balloon in the air is owing to its levity, as the gas that fills it is lighter than common air.
2. Lightness of temper or conduct; inconstancy; changeableness; unsteadiness; as, the levity of youth. – Hooker.
3. Want of due consideration; vanity; freak. He never employed his omnipotence out of levity or ostentation.
4. Gayety of mind want of seriousness; disposition to trifle. The spirit of religion and seriousness was succeeded by levity.