Webster’s Revised Unabridged Dictionary · 1913
Authenticity
Au′then·tic′i·ty (a̤′thĕn·tĭs′ĭ·ty̆), n. [Cf. F. authenticité.] 1. The quality of being authentic or of established authority for truth and correctness.
2. Genuineness; the quality of being genuine or not corrupted from the original.
☞ In later writers, especially those on the evidences of Christianity, authenticity is often restricted in its use to the first of the above meanings, and distinguished from qenuineness.