A binary string that is used as an initial value in computing the first iteration in feedback mode. It may be an empty string.
Source(s):
NIST SP 800-108 under IV

  A binary vector used as the input to initialize the algorithm for the encryption of a plaintext block sequence to increase security by introducing additional cryptographic variance and to synchronize cryptographic equipment. The initialization vector need not be secret. Some of the Triple Data Encryption Algorithm Modes of Operation require 3 initialization vectors.
Source(s):
NIST SP 800-20 under Initialization Vector

  Initialization Vector
Source(s):
NIST SP 800-20 under IV
NIST SP 800-38D under IV

  A data block that some modes of operation require as an additional initial input.
Source(s):
NIST SP 800-38A

  The initialization vector.
Source(s):
NIST SP 800-38A under IV
NIST SP 800-38D under IV

  A nonce that is associated with an invocation of authenticated encryption on a particular plaintext and AAD.
Source(s):
NIST SP 800-38D under Initialization Vector

  A vector used in defining the starting point of a cryptographic process.
Source(s):
NIST SP 800-57 Part 1 Rev. 4 [Superseded] under Initialization vector (IV)
NIST SP 800-57 Part 1 Rev. 5 under Initialization vector (IV)
NIST SP 800-175B Rev. 1
NIST SP 800-57 Part 1 Rev. 3 [Superseded] under Initialization vector (IV)

  A vector used in defining the starting point of an encryption process within a cryptographic algorithm.
Source(s):
NIST SP 800-57 Part 2 [Superseded] under Initialization vector (IV)

  A vector used in defining the starting point of a cryptographic process (e.g., encryption and key wrapping).
Source(s):
NIST SP 800-57 Part 2 Rev.1