ra·​dio·​ther·​a·​py | \ ˌrā-dē-ō-ˈther-ə-pē How to pronounce radiotherapy (audio) \

Definition of radiotherapy

: the treatment of disease with radiation (such as X-rays)

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Other Words from radiotherapy

radiotherapist \ ˌrā-​dē-​ō-​ˈther-​ə-​pist How to pronounce radiotherapy (audio) \ noun

Examples of radiotherapy in a Sentence

Recent Examples on the Web Authorities are prioritizing the recovery of systems involved in patient diagnostics, such as radiology, radiotherapy and maternity and newborn services. Sylvia Hui, Star Tribune, 18 May 2021 After a hard and courageous battle through chemotherapy and radiotherapy, Sean received the all-clear the following July 2019 and is still officially in remission. Tommy Williams, Forbes, 9 Apr. 2021 Treating cancer more effectively Linear electron acceleration has long been used in radiotherapy to create X-rays for treating cancer. Andrea Willige, Forbes, 18 Mar. 2021 Combining radiotherapy with immunotherapy in novel ways can enhance results, by improving the immune system’s cancer recognition and rendering tumors less immunosuppressive. David L. Coddon, San Diego Union-Tribune, 25 Feb. 2021 Chemotherapy and radiotherapy notoriously cause a whole host of debilitating side effects, such as exhaustion, nausea and vomiting, and mood changes. Genevieve Richardson, SELF, 7 Dec. 2020 The Wanted, is currently undergoing radiotherapy and chemotherapy treatment for an inoperable brain tumor. Rosy Cordero,, 12 Oct. 2020 Unlike Brown, Castillejo underwent only one stem-cell transplantation instead of two and did not have radiotherapy to his entire body as part of his treatment. Alisha Ebrahimji And Jacqueline Howard, CNN, 30 Sep. 2020 It has been used for decades to treat patients undergoing chemotherapy and radiotherapy for cancer. Scientific American, 10 Dec. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'radiotherapy.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of radiotherapy

1902, in the meaning defined above

History and Etymology for radiotherapy

International Scientific Vocabulary

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Time Traveler for radiotherapy

Time Traveler

The first known use of radiotherapy was in 1902

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Statistics for radiotherapy

Last Updated

27 May 2021

Cite this Entry

“Radiotherapy.” Dictionary, Merriam-Webster, Accessed 19 Jun. 2021.

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More Definitions for radiotherapy


ra·​dio·​ther·​a·​py | \ ˌrād-ē-ō-ˈther-ə-pē How to pronounce radiotherapy (audio) \
plural radiotherapies

Medical Definition of radiotherapy

: the treatment of disease by means of radiation (as X-rays)

called also radiation therapy, radium therapy

— compare radiodiagnosis

More from Merriam-Webster on radiotherapy Encyclopedia article about radiotherapy


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