A digital certificate containing a public key for an entity and a unique name for that entity together with some other information that is rendered un-forgeable by the digital signature of the certification authority that issued the certificate, which is encoded in the format defined in the ISO/ITU-T X.509 standard.
Source(s):
NIST SP 800-57 Part 1 Rev. 5 under X.509 public-key certificate

  The public key for a user (or device) and a name for the user (or device), together with some other information, rendered unforgeable by the digital signature of the certification authority that issued the certificate, encoded in the format defined in the ISO/ITU-T X.509 standard. Also known as X.509 Certificate.
Source(s):
CNSSI 4009-2015 [Superseded] from NIST SP 800-57 Part 1 Rev. 3 - Adapted

  A digital certificate containing a public key for entity and a name for the entity, together with some other information that is rendered un- forgeable by the digital signature of the certification authority that issued the certificate, encoded in the format defined in the ISO/ITU-T X.509 standard.
Source(s):
NIST SP 800-57 Part 1 Rev. 3 [Superseded] under X.509 public-key certificate

  A digital certificate containing a public key for an entity and a name for that entity, together with some other information that is rendered un-forgeable by the digital signature of the certification authority that issued the certificate, encoded in the format defined in the ISO/ITU-T X.509 standard.
Source(s):
NIST SP 800-57 Part 1 Rev. 4 [Superseded] under X.509 public-key certificate