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)

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 Surgery is still the main way of removing tumors, but after X-rays were discovered in 1895, radiotherapy soon became used too. New York Times, 25 May 2022 People who received all three treatments had the highest rates of depression and anxiety, and chemotherapy was linked to significantly higher rates of psychiatric disorders compared to those who only received radiotherapy. Julia Ries,, 7 Apr. 2022 After eight months of treatment, including chemotherapy, radiotherapy, and an ongoing clinical trial, she was given the all-clear. People Staff,, 30 Mar. 2022 His son Noah was diagnosed with liver cancer in 2016 but has been in remission since 2017 following chemotherapy and radiotherapy. Keith Caulfield, Billboard, 23 Mar. 2022 Secondly, as reported by NBC and others, Powell had a type of cancer called multiple myeloma, a type of blood cancer which can sometimes be controlled for several years using chemotherapy, radiotherapy and immunotherapy treatments. Victoria Forster, Forbes, 18 Oct. 2021 Healthcare providers can use machine learning in combination with a cancer patient’s medical scans, lab tests and EHR data for generating a safer radiotherapy regimen. Sergey Avdeychik, Forbes, 29 Oct. 2021 Cancer is a disease in which cells in the body abnormally and uncontrollably grow and multiply, according to Dr. Henry Park, chief of thoracic radiotherapy at Yale Medicine. Sudiksha Kochi, USA TODAY, 21 Oct. 2021 The Instagram post, liked about 100 times in the first day online, adds that biopsy, radiotherapy and chemotherapy are harmful. Sudiksha Kochi, USA TODAY, 21 Oct. 2021 See More

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.

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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Dictionary Entries Near radiotherapy

radio telescope



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Statistics for radiotherapy

Last Updated

7 Aug 2022

Cite this Entry

“Radiotherapy.” Dictionary, Merriam-Webster, Accessed 9 Aug. 2022.

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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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