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 /

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

• radiotherapist
  noun
• radiotherapeutic
  adjective
• radiotherapeutically
  adverb

Etymology

Origin of radiotherapy

First recorded in 1900–05; radio- + therapy

Example Sentences

See Examples For:

radiotherapy

McClean underwent stereotactic radiosurgery, which is a precise form of radiotherapy that delivers a high dose of radiation to a targeted area within the brain.

From BBC ● Sep. 8, 2026

She was first diagnosed with triple negative breast cancer, external five years ago, which was successfully treated with intravenous chemotherapy, a lumpectomy and radiotherapy, followed by oral chemotherapy.

From BBC ● Sep. 7, 2026

The blood-brain barrier creates another obstacle by restricting how effectively drugs and radiotherapy can reach the tumor.

From Science Daily ● Aug. 27, 2026

She subsequently underwent brain surgery, radiotherapy and chemotherapy in an effort to keep the cancer at bay.

From Los Angeles Times ● Jul. 14, 2026

This is despite Healthineers’ growth prospects and leading position and margins in imaging and radiotherapy, the analysts write.

From The Wall Street Journal ● Jul. 9, 2026