Well there was no medieval word for the Crusades. There were various vernacular words linked to the cross; there were Latin words about people who took the cross – you became a cruce signatus, a bearer of the cross, because to become a crusader you went through a ceremony where you were given a physical cross which you wore on your clothing, usually made of cloth that you wore on your shoulder. So these were “cross bearers”, following the biblical injunction “Take up your cross and follow me”. So these words merged in vernacular terms and by the 13th, 14th century, i.e. 150, 200 years after the beginning of the Crusades, you have vernacular terms that aren’t general but they’re localised for the Crusades. And so by the early modern period there are various words like crusado and crusade. Crusado is a Spanish version, croisade is French. The English “Crusade” only really gets adopted in the 18th century.