Radiation therapy

n. treatment of diseases by exposure to high-energy radiation from radioactive sources, use of radiation to damage cancer cells, radiotherapy

Radiation therapy (or radiotherapy) is the medical use of ionizing radiation as part of cancer treatment to control malignant cells (not to be confused with radiology, the use of radiation in medical imaging and diagnosis). Radiotherapy may be used for curative or adjuvant cancer treatment. It is used as palliative treatment (where cure is not possible and the aim is for local disease control or symptomatic relief) or as therapeutic treatment (where the therapy has survival benefit but is not curative).  Total body irradiation (TBI) is a radiotherapy technique used to prepare the body to receive a bone marrow transplant. Radiotherapy has a few applications in non-malignant conditions, such as the treatment of  trigeminal neuralgia, severe thyroid eye disease,  pterygium, prevention of keloid scar growth, and prevention of heterotopic ossification. The use of radiotherapy in non-malignant conditions is limited partly by worries about the risk of radiation-induced cancers.
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Radiation therapy, sometimes called radiotherapy, x-ray therapy radiation treatment, cobalt therapy, electron beam [more]Radiation therapy - Community and Resources

Noun
1. (medicine) the treatment of disease (especially cancer) by exposure to radiation from a radioactive substance
(synonym) radiotherapy, radiation, actinotherapy, irradiation
(hypernym) therapy
(hyponym) phototherapy
(classification) medicine, medical specialty

Radiation therapy is the use of special high energy x-ray beams to kill rapidly growing cells, such as cancer cells. It is a generally a painless treatment and is given in an outpatient setting without the need for hospitalization.