radiotherapy

noun

ra·​dio·​ther·​a·​py ˌrā-dē-ō-ˈther-ə-pē 

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

radiotherapist

ˌrā-dē-ō-ˈther-ə-pist 

noun

Examples of radiotherapy in a Sentence

Recent Examples on the Web

Novartis’s radioligand therapy targets mutations in tumors, delivering radiation only where it is needed, unlike ordinary radiotherapy which kills non-cancerous cells as well as cancerous ones. —semafor.com, 5 Sep. 2025

Certain cancer treatments, like radiotherapy (high-energy x-rays that destroy cancer cells) 1 Risk Factors While anyone can develop lockjaw, certain individuals are at a greater risk. —Mark Gurarie, Health, 22 Aug. 2025

Following the procedure, Barbery underwent six weeks of chemotherapy and radiotherapy. —Reem Amro, FOXNews.com, 11 Aug. 2025

Undergoing treatment In 2021, Dieu spent six months undergoing radiotherapy in the Dominican Republic for his cancer. —Miami Herald, 29 July 2025

Word History

Etymology

International Scientific Vocabulary

First Known Use

1902, in the meaning defined above

Rhymes for radiotherapy

• brachytherapy
• chemotherapy
• cryotherapy
• hydrotherapy
• hypnotherapy
• monotherapy
• phototherapy
• psychotherapy
• sclerotherapy
• immunotherapy
• pharmacotherapy
• physiotherapy

Medical Definition

radiotherapy

noun

ra·​dio·​ther·​a·​py ˌrād-ē-ō-ˈther-ə-pē 

plural radiotherapies

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

called also radiation therapy, radium therapy

compare radiodiagnosis