The term FIRMLY FIX can be solved by the crossword solutions CEMENT (6 letters) and EMBED (5 letters). CEMENT is a binding material made from a mixture of materials such as limestone, clay, and sand that is heated to form a hard substance. It is commonly used in construction to hold together bricks, stones, and other materials. EMBED is a verb meaning to fix firmly in place or to enclose something within something else. It is often used to describe the process of placing an object into a material such as CEMENT or soil.