Search Result for "lightheartedness": 
Wordnet 3.0

NOUN (1)

1. the cheerful feeling you have when nothing is troubling you;
[syn: carefreeness, insouciance, lightheartedness, lightsomeness]


The Collaborative International Dictionary of English v.0.48:

Light-hearted \Light"-heart`ed\ (l[imac]t"h[aum]rt`[e^]d), a. Free from grief or anxiety; gay; cheerful; merry. -- Light"-heart`ed*ly, adv. -- Light"-heart`ed*ness, n. [1913 Webster]
WordNet (r) 3.0 (2006):

lightheartedness n 1: the cheerful feeling you have when nothing is troubling you [syn: carefreeness, insouciance, lightheartedness, lightsomeness]