Individual or (system) process authorized to access an information system.
Sources:
NIST SP 800-18 Rev. 1 under User from CNSSI 4009

  See Information System User
Sources:
NIST SP 800-128 under User

  An FCKMS role that utilizes the key-management services offered by an FCKMS service provider.
Sources:
NIST SP 800-152 under User

  A human entity.
Sources:
NIST SP 800-57 Part 2 Rev.1 under User

  Individual, or (system) process acting on behalf of an individual, authorized to access an information system. [Note: With respect to SecCM, an information system user is an individual who uses the information system functions, initiates change requests, and assists with functional testing.]
Sources:
NIST SP 800-128 from CNSSI 4009

  An individual (person). Also see Entity.
Sources:
NIST SP 800-57 Part 1 Rev. 5 under User

  Person who interacts with the product.
Sources:
NISTIR 8040 under User from ISO 9241-11:1998

  A person, organization, or other entity which requests access to and uses the resources of a computer system or network.
Sources:
NISTIR 4734 under User

  The entity, human or machine, that is identified by the userID, authenticated prior to system access, the subject of all access control decisions, and held accountable via the audit reporting system.
Sources:
NISTIR 5153 under User

  the set of people, both trusted (e.g., administrators) and untrusted, who use the system.
Sources:
NISTIR 6192 under User

  A consumer of the services offered by an RP.
Sources:
NISTIR 8149 under User

  A person, team, or organization that accesses or otherwise uses an OLIR.
Sources:
NIST IR 8278Ar1 under User
NIST IR 8278r1 under User