The term 'cookout supply' can be broken down into two crossword solutions: BUNS (4 letters) and supplies. BUNS are a type of bread roll that is often served at cookouts, barbecues, and other outdoor events. Supplies refer to the various items needed to host a successful cookout, such as charcoal, utensils, condiments, and food. Together, BUNS and supplies make up the necessary components for a successful cookout.