# radiotherapy

/ɹˌeɪdɪəʊθˈɛɹəpi/ (UK) · CEFR C1 · Noun

Source: https://englishreference.com/word/radiotherapy
Updated: 2026-05-09

## Definition

a medical treatment that uses high-energy rays to kill cancer cells or shrink tumors. Doctors often use it alongside surgery or other medicines to help patients get better.

For teachers: the treatment of disease, especially cancer, using ionizing radiation to destroy malignant cells. Often administered in fractionated doses to allow healthy tissue to recover between sessions.

## Examples

- The patient started radiotherapy to shrink the tumor before surgery.
- After the surgeon removed the primary mass, the patient underwent six weeks of radiotherapy to ensure no cancer cells remained.
- Advances in medical imaging allow clinicians to target radiotherapy with extreme precision, minimizing damage to the healthy organs surrounding the site of the malignancy.

## Usage notes

- Uncountable when referring to the medical field or the general treatment method.

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