Official with the authority to formally assume responsibility for operating an information system at an acceptable level of risk to agency operations (including mission, functions, image, or reputation), agency assets, or individuals. Synonymous with Accreditation Authority.
Sources:
FIPS 200 under AUTHORIZING OFFICIAL
NIST SP 800-60 Vol. 1 Rev. 1 under Authorizing Official from FIPS 200
NIST SP 800-60 Vol. 2 Rev. 1 under Authorizing Official from FIPS 200

  A senior (federal) official or executive with the authority to formally assume responsibility for operating an information system at an acceptable level of risk to organizational operations (including mission, functions, image, or reputation), organizational assets, individuals, other organizations, and the Nation.
Sources:
CNSSI 4009-2015
NIST SP 800-128 under Authorizing Official from CNSSI 4009
NIST SP 800-137 under Authorizing Official (AO) from CNSSI 4009

  Senior (federal) official or executive with the authority to formally assume responsibility for operating an information system at an acceptable level of risk to organizational operations (including mission, functions, image, or reputation), organizational assets, individuals, other organizations, and the Nation.
Sources:
NIST SP 800-30 Rev. 1 under Authorizing Official from CNSSI 4009
NIST SP 800-39 under Authorizing Official from CNSSI 4009

  Official with the authority to formally assume responsibility for operating an information system at an acceptable level of risk to agency operations (including mission, functions, image, or reputation), agency assets, or individuals.
Sources:
NIST SP 800-18 Rev. 1 under Authorizing Official

  A senior (federal) official or executive with the authority to formally assume responsibility for operating a system at an acceptable level of risk to organizational operations (including mission, functions, image, or reputation), organizational assets, individuals, other organizations, and the Nation.
Sources:
NIST SP 800-12 Rev. 1 under Authorizing Official (AO)

  A senior Federal official or executive with the authority to authorize (i.e., assume responsibility for) operation of an information system or the use of a designated set of common controls at an acceptable level of risk to agency operations (including mission, functions, image, or reputation), agency assets, individuals, other organizations, and the Nation.
Sources:
NIST SP 800-128

  See Authorizing Official.
Sources:
NIST SP 800-18 Rev. 1 under Accrediting Authority
NIST SP 800-60 Vol. 1 Rev. 1 under Accrediting Authority
NIST SP 800-60 Vol. 2 Rev. 1 under Accrediting Authority

  A senior Federal official or executive with the authority to authorize (i.e., assume responsibility for) the operation of an information system or the use of a designated set of common controls at an acceptable level of risk to agency operations (including mission, functions, image, or reputation), agency assets, individuals, other organizations, and the Nation.
Sources:
NIST SP 800-161r1 from NIST SP 800-53 Rev. 5
NIST SP 800-37 Rev. 2 from OMB Circular A-130 (2016)
NIST SP 800-53 Rev. 5 from OMB Circular A-130 (2016)
NIST SP 800-53A Rev. 5 from OMB Circular A-130 (2016)
NIST SP 800-53B from OMB Circular A-130 (2016)

  Senior federal official or executive with the authority to formally assume responsibility for operating an information system at an acceptable level of risk to organizational operations (including mission, functions, image, or reputation), organizational assets, individuals, other organizations, and the Nation.
Sources:
NISTIR 7622 under Authorizing Official