What is an antonym for authenticity?

Here are some antonyms for authenticity, depending on the specific context:

General Antonyms:

* Fakeness

* Artificiality

* Counterfeit

* Imitation

* Forgery

* Fraud

* Inauthenticity

* Phony

* Sham

* Fake

More Specific Antonyms:

* Unoriginality (if referring to originality)

* Inaccuracy (if referring to truthfulness)

* Insincerity (if referring to genuine emotions)

* Deception (if referring to honesty)

* Fabrication (if referring to being made up)

* Simulation (if referring to being real)

The best antonym for "authenticity" will depend on the specific situation. For example, if you are talking about a fake painting, "counterfeit" would be a good antonym. If you are talking about a person who is not genuine, "insincere" would be a better choice.