WordNet (r) 3.0 (2006):

baud rate
    n 1: (computer science) a data transmission rate (bits/second)
         for modems [syn: baud, baud rate]

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

baud
baud rate

    /bawd/ (plural "baud") The unit in
   which the information carrying capacity or "signalling rate"
   of a communication channel is measured.  One baud is one
   symbol (state-transition or level-transition) per second.
   This coincides with bits per second only for two-level
   modulation with no framing or stop bits.

   A symbol is a unique state of the communication channel,
   distinguishable by the receiver from all other possible
   states.  For example, it may be one of two voltage levels on a
   wire for a direct digital connection or it might be the phase
   or frequency of a carrier.

   The term "baud" was originally a unit of telegraph signalling
   speed, set at one Morse code dot per second.  Or, more
   generally, the reciprocal of the duration of the shortest
   signalling element.  It was proposed at the International
   Telegraph Conference of 1927, and named after J.M.E. Baudot
   (1845-1903), the French engineer who constructed the first
   successful teleprinter.

   The UK PSTN will support a maximum rate of 600 baud but each
   baud may carry between 1 and 16 bits depending on the coding
   (e.g. QAM).

   Where data is transmitted as packets, e.g. characters, the
   actual "data rate" of a channel is

   	R D / P

   where R is the "raw" rate in bits per second, D is the number
   of data bits in a packet and P is the total number of bits in
   a packet (including packet overhead).

   The term "baud" causes much confusion and is usually best
   avoided.  Use "bits per second" (bps), "bytes per second" or
   "characters per second" (cps) if that's what you mean.

   (1998-02-14)