perhaps from Middle French dialect (Norman-Picard) canter to tell, literally, to sing, from Latin cantare — more at chant
Noun (2) and Verb (2)
Middle English cant side, probably from Middle Dutch or Middle French dialect; Middle Dutch, edge, corner, from Middle French dialect (Picard), from Latin canthus, cantus iron tire, perhaps of Celtic origin; akin to Welsh cant rim; perhaps akin to Greek kanthos corner of the eye
Adjective (2)
Middle English, probably from Middle Low German *kant