Thermochemical is an adjective that relates to the study of the relationship between heat and chemical reactions. Synonyms for thermochemical include thermodynamic, calorific, heat-based, and heat-transferential. These words all represent the same concept, describing the interaction between heat and chemical processes. Another synonym for thermochemical is exothermic, which refers to a chemical reaction that releases energy in the form of heat. From chemical engineering to the study of combustion, understanding thermochemical processes is critical for scientists and engineers in a variety of fields. Whatever the term used, the principles at work are the same and must be correctly identified and utilized.