The property of being lighthearted, joyous, cheerful, without a care.(noun)
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Use "lightheartedness" in a sentence
"The "joke" part of his comments only came out after the comments were made to assure a sense of lightheartedness from the Polish keeper."
"Na's textural images recall the lightheartedness and limpid charm of Paul Klee."
"In so doing he enables director Danny Boyle "Slumdog Millionaire,""Shallow Grave,""Trainspotting" to tell a story going in an inevitably gruesome direction with a kind of lightheartedness that makes it both bearable and entertaining."