"Chevalerie" a word for knighthood is from an old French word. Chivalry referred as warfare wherein obtaining fortune and fame in their king's name and without any cowardliness during the war. In other words, chivalry refers to the ideal qualification of a knight which includes valor, generosity, dexterity, and courtesy in arms.
Hence, the best definition of chivalry would be, the behavior and conduct expected of medieval knights
It referred to more of making the profit during a war and joining the military for its offers and pouring money from war business.