V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

AAC
       Advanced Audio Coding (IIS, MPEG, AT&T, Dolby, Sony, ...)


V.E.R.A. -- Virtual Entity of Relevant Acronyms (February 2016):

AAC
       Authorization and Access Control (IETF)


The Free On-line Dictionary of Computing (30 December 2018):

Advanced Audio Coding
AAC