Antonyms of noun unfaithfulness

1 sense of unfaithfulness

Sense 1
infidelity, unfaithfulness -- (the quality of being unfaithful)
       Antonym of faithfulness (Sense 1)
      => fidelity, faithfulness -- (the quality of being faithful)

Synonyms/Hypernyms (Ordered by Estimated Frequency) of noun unfaithfulness

1 sense of unfaithfulness

Sense 1
infidelity, unfaithfulness -- (the quality of being unfaithful)
       => quality -- (an essential and distinguishing attribute of something or someone; "the quality of mercy is not strained"--Shakespeare)