A hard, yellowish deposit on the teeth, consisting of organic secretions and food particles deposited in various salts, such as calcium carbonate.

• 牙垢，牙结石一种牙齿上的坚硬的浅黄色沉淀物，包含有机分泌物和各种以盐（如，碳酸钙）的形式沉淀下来的食物微粒