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]WordNet (r) 3.0 (2006):
cantering adj 1: riding at a gait between a trot and a gallop; "the cantering soldiers"