What does "light-mindedness" mean?

The quality or state of one who is light-minded; lack of seriousness.

What is a synonym for "light-mindedness"?

Common synonyms include: flippancy.

noun

noun ·Rare ·Advanced level

Noun

1
The quality or state of one who is light-minded; lack of seriousness. uncountable
2
inappropriate levity wordnet

From light-minded (adjective) + -ness (suffix forming nouns).