Fortifies is a term used to describe the process of making something stronger or more secure. It is often used in the context of military fortifications, such as building walls or other structures to protect a city or area from attack. Fortifying can also refer to strengthening a structure or object, such as reinforcing a door or window with additional locks or bars. The term 'STEELS' is a synonym for fortifies, and is often used to describe the process of hardening metal objects by heating them and then cooling them quickly.