The phrase "to use something as a dip" means to take something, such as a food item or condiment, and put it into a liquid in order to create a sauce or coating that can be used for dipping other foods. This is commonly done with chips, vegetables, or bread, among many others. The term "dip" refers to the liquid base into which the ingredient is placed, and the resulting mixture is then used as a dip for various snacks or meals.