The Collaborative International Dictionary of English v.0.48:

Canter \Can"ter\ (k[a^]n"t[~e]r), n. [An abbreviation of
   Canterbury. See Canterbury gallop, under Canterbury.]
   1. A moderate and easy gallop adapted to pleasure riding.
      [1913 Webster]

   Note: The canter is a thoroughly artificial pace, at first
         extremely tiring to the horse, and generally only to be
         produced in him by the restraint of a powerful bit,
         which compels him to throw a great part of his weight
         on his haunches . . . There is so great a variety in
         the mode adopted by different horses for performing the
         canter, that no single description will suffice, nor
         indeed is it easy . . . to define any one of them. --J.
         H. Walsh.
         [1913 Webster]

   2. A rapid or easy passing over.
      [1913 Webster]

            A rapid canter in the Times over all the topics.
                                                  --Sir J.
                                                  Stephen.
      [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Canter \Can"ter\ (k[a^]n"t[~e]r), v. i. [imp. & p. p. Cantered
   (k[a^]n"t[~e]rd); p. pr. & vb. n. Cantering.]
   To move in a canter.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Canter \Can"ter\, v. t.
   To cause, as a horse, to go at a canter; to ride (a horse) at
   a canter.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Canter \Cant"er\, n.
   1. One who cants or whines; a beggar.
      [1913 Webster]

   2. One who makes hypocritical pretensions to goodness; one
      who uses canting language.
      [1913 Webster]

            The day when he was a canter and a rebel.
                                                  --Macaulay.
      [1913 Webster]

WordNet (r) 3.0 (2006):

canter
    n 1: a smooth three-beat gait; between a trot and a gallop [syn:
         canter, lope]
    v 1: ride at a canter; "The men cantered away"
    2: go at a canter, of horses
    3: ride at a cantering pace; "He cantered the horse across the
       meadow"

Moby Thesaurus II by Grady Ward, 1.0:

98 Moby Thesaurus words for "canter":
   Holy Willie, Joseph Surface, Mawworm, Pecksniff, Pharisee,
   Tartuffe, affecter, amble, bound, bum, burst, burst of speed,
   canting hypocrite, caracole, curvet, dash, dead run, derelict,
   dissembler, dissimulator, dogtrot, drifter, fair-weather friend,
   false friend, flank speed, flat-out speed, forced draft, formalist,
   fox-trot, frisk, full gallop, gallop, get, git, go on horseback,
   hack, hand gallop, headlong rush, heavy right foot, high lope,
   hightail, hobo, hop, hop along, hotfoot, hypocrite, jog trot, leap,
   lip server, lip worshiper, lope, make tracks, maximum speed,
   mealymouth, mount, open throttle, pace, pharisee, phony, piaffe,
   pietist, pious fraud, plunge, poser, prance, race, ranter,
   religionist, religious hypocrite, ride bareback, ride hard, run,
   rush, sanctimonious fraud, scamper, scud, scurry, scuttle,
   sniveler, snuffler, spiritual humbug, spring, sprint, spurt, step,
   step along, step lively, street arab, summer soldier, take horse,
   tittup, tramp, trip, trot, vag, vagrant, whited sepulcher,
   wide-open speed