Definition of cheerfulness in English:

cheerfulness

noun

  • 1The quality or state of being noticeably happy and optimistic.

    ‘her brand of hearty cheerfulness’
    ‘it's hard to be grumpy in the face of their resolute cheerfulness’
    1. 1.1The quality of causing happiness.
      ‘the cheerfulness from the fire’
      ‘the overall cheerfulness of the film’

Pronunciation

cheerfulness

/ˈtʃɪəfəlnəs/