levity

noun

Etymology: Coined in 1564, from Latin levitās (“lightness, frivolity”), from levis (“lightness (in weight)”). Cognate to lever, and more distantly, light.

1. A lightness of manner or speech, frivolity; flippancy; a lack of appropriate seriousness; an inclination to make a joke of serious matters.

   “An attempt to inject a little levity into the proceedings.”

2. A lack of steadiness.
3. The state or quality of being light, buoyancy.

   “Most of the confidences were unsought - frequently I have feigned sleep, preoccupation or a hostile levity […]”

   “[…]it would really seem as if there was something nomadic in our natures, a principle of levity and restlessness […]”

4. A lighthearted or frivolous act.

   “For though it be something wonderful to tell that any should have hearts so hardened, in the midst of such a calamity, as to rob and steal, yet certain it is that all sorts of villainies, and even levities and debaucheries, were then practiced in the town as openly as ever: I will not say quite as frequently, because the number of people were many ways lessened.”

   “[…] or do the people joy less than common in their levities?"”