Cortain is a legendary short sword in the legend of Ogier the Dane. This name is the accusative case declension of Old French corte, meaning "short".

Ogier the Dane is a legendary paladin of Charlemagne who appears in many Old French chansons de geste. In particular, he features as the protagonist in La Chevalerie Ogier, which belongs to the Geste de Doon de Mayence. The first part of this epic, the enfance[s] of Ogier, is marked by his duel against a Saracen from whom he obtains the sword Cortain, followed by victory over another Saracen opponent from whom he wins the horse Broiefort. In subsequent parts, Ogier turns into a rebel with cause, seeking refuge with the King of Lombardy and warring with Charlemagne for many years, until he is eventually reconciled when a dire need for him emerges after another Saracen incursion.