Authenticated Encryption definition in Computer Security terms:
Definition(s): A function in which plaintext is encrypted into ciphertext, and a MAC is generated on the plaintext or ciphertext and, optionally, on associated data that is not encrypted.
Source(s): NIST SP 800-132
The function of GCM in which the plaintext is encrypted into the ciphertext, and an authentication tag is generated on the AAD and the ciphertext.
Source(s): NIST SP 800-38D
reference: CSRC Glossary