WordNet (r) 3.0 (2006):

data rate
    n 1: the rate at which circuits or other devices operate when
         handling digital information

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

data transfer rate
data rate
transfer rate

    (Or "throughput, data rate", "transmission
   rate") The amount of data transferred in one direction over
   a link divided by the time taken to transfer it, usually
   expressed in bits per second (bps), bytes per second (Bps) or
   baud.  The link may be anything from an interface to a hard
   disk to a radio transmission from a satellite.

   Where data transfer is not continuous throughout the given
   time interval, the data transfer rate is thus an average rate
   that will be lower than the peak rate.  The peak or maximum
   possible rate may itself be lower than the capacity of the
   communication channel if the channel is shared, or part of the
   signal is not considered as data, e.g. checksum or routing
   information.

   When applied to data rate, the multiplier prefixes "kilo-",
   "mega-", "giga-", etc. (and their abbreviations, "k", "M",
   "G", etc.) always denote powers of 1000.  For example, 64 kbps
   is 64,000 bits per second.  This contrasts with units of
   storage where they stand for powers of 1024, e.g. 1 KB =
   1024 bytes.

   The other important characteristic of a channel is its
   latency.

   The bandwidth of a channel determines the data transfer rate
   but is a different characteristic, measured in Hertz.
   [Relationship?]

   (2008-02-08)