radiotherapy

American  

[rey-dee-oh-ther-uh-pee] / ˌreɪ di oʊˈθɛr ə pi /

noun

Medicine/Medical.

1. treatment of disease by means of x-rays or of radioactive substances.

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radiotherapy British  

/ ˌreɪdɪəʊˈθɛrəpɪ, ˌreɪdɪəʊˌθɛrəˈpjuːtɪk /

noun

1. the treatment of disease, esp cancer, by means of alpha or beta particles emitted from an implanted or ingested radioisotope, or by means of a beam of high-energy radiation Compare chemotherapy

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Other Word Forms

• radiotherapeutic
  adjective
• radiotherapeutically
  adverb
• radiotherapist
  noun

Etymology

Origin of radiotherapy

First recorded in 1900–05; radio- + therapy

Example Sentences

Alastair then underwent a month of radiotherapy and was given the all-clear in February.

From BBC • May 6, 2026

These patients often undergo radiotherapy near the mouth, which can damage salivary glands and reduce saliva production.

From Science Daily • Apr. 5, 2026

As the cancer had not spread, the father of three did not need chemotherapy or radiotherapy and was back working within six months.

From BBC • Mar. 31, 2026

Julia Endacott works as a women's health physiotherapist and finished radiotherapy for breast cancer two weeks ago.

From BBC • Mar. 23, 2026

As part of her treatment, she needed radiotherapy followed by an operation to remove two muscles from her right thigh, which left her with minimal movement.

From BBC • Mar. 16, 2026