Plural of 'authenticity': multiple instances or types of genuine quality or the state of being real and not fake.
From 'authenticity' (from 'authentic') + '-ies' (plural suffix). The noun 'authenticity' emerges in English by the 18th century.
Philosophers and artists debate 'authenticities' as plural because different cultures value different markers of realness—what proves authenticity in folk music isn't what proves it in fashion or food.
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