Raising the temperature is a phrase that refers to increasing the heat level in a particular environment. Some synonyms for raising the temperature include heating up, warming up, and elevating the degree. Other words one can use as a substitute for this phrase are increasing the warmth, adding heat, or intensifying the temperature. Slang terms that are often used as synonyms for raising the temperature include cranking up the heat, turning up the heat, and stoking the fire. Whatever word one uses, it all boils down to the same meaning of increasing the temperature level in a particular space.