Radiation therapy, commonly known as ray therapy, is a medical treatment that uses high-energy radiation to destroy cancer cells and shrink tumors. While "ray therapy" is a common term used in the medical field, there are several other synonyms that health professionals may use to refer to this treatment. These synonyms include radiation oncology, radiotherapy, and irradiation. Other related terms may include brachytherapy, proton therapy, and external beam radiation therapy. Although the term ray therapy is the most commonly used term, it is important to be familiar with the other synonyms in order to facilitate clear communication with healthcare providers and patients.