Vulcanizing is the process of chemically treating rubber or other materials to make them stronger and more durable. Some synonyms for the word vulcanizing include toughening, curing, hardening, and fortifying. Other words that may be used as synonyms include solidifying, strengthening, and reinforcing. Each of these words emphasizes the idea of improving the physical strength and durability of a material by subjecting it to specific chemical processes. While each of these words has a slightly different connotation, they are all commonly used to describe the process of making rubber or other materials stronger and better able to withstand wear and tear.