Synonyms for Falseness (same or very similar meaning)
WordNet sense 1 (the state of being false or untrue):
falsity
WordNet sense 2 (unfaithfulness by virtue of being unreliable or treacherous):
faithlessness, fickleness, inconstancy
WordNet sense 3 (the quality of not being open or truthful; deceitful or hypocritical):
hollowness, insincerity
From the ODE community, based on WordNet
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