Radiotherapy (noun)

The treatment of disease, especially cancer, by exposure to a radioactive substance.

Origin:

Early 20th century: from radi- + -therapy.

Examples:

1. The patient will have to undergo radiotherapy.
2. Radiotherapy is a common treatment for cancer.
3. Radiotherapy can cause side effects such as fatigue and skin irritation.
4. The radiotherapy was successful in shrinking the tumor.
5. Radiotherapy is often used in combination with chemotherapy.