The term 'grill bit' refers to a type of cooking tool used to cook food over an open flame. The crossword solutions for this term are ASH (3 letters), EMBER (5 letters), and CINDER (6 letters). ASH is the residue left after something has been burned, while an EMBER is a glowing, red-hot coal or wood fragment that is still burning. A CINDER is a small piece of partially burned coal or wood. All three of these terms are related to the process of grilling food over an open flame.