radiotherapy

noun

ra·​dio·​ther·​a·​py ˌrā-dē-ō-ˈther-ə-pē How to pronounce radiotherapy (audio)
: the treatment of disease with radiation (such as X-rays)
radiotherapist
ˌrā-dē-ō-ˈther-ə-pist How to pronounce radiotherapy (audio)
noun

Examples of radiotherapy in a Sentence

Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
His age, recent back-to-back bouts of cancer and ongoing radiotherapy complications notwithstanding, Book’s drive is so tireless that it’s become something of a reverential joke among many who interact with him. — Max Klaver, Miami Herald, 20 Mar. 2025 By some estimates, there have been approximately 4,200 deaths attributed to nuclear reactor incidents since 1945 (not counting radiotherapy accidents or Soviet submarine failures). — Reader Commentary, Baltimore Sun, 10 Feb. 2025 That approach, which uses the body’s immune system to target cancer cells, is less invasive than more traditional cancer-fighting treatments like chemotherapy and radiotherapy but is only effective for a subset of people. — Mack Degeurin, Popular Science, 8 Jan. 2025 Beattie played through her radiotherapy treatments and is now cancer-free. — Anne M. Peterson, San Diego Union-Tribune, 2 Feb. 2024 See All Example Sentences for radiotherapy

Word History

Etymology

International Scientific Vocabulary

First Known Use

1902, in the meaning defined above

Time Traveler
The first known use of radiotherapy was in 1902

Rhymes for radiotherapy

See All Rhymes for radiotherapy

Browse Nearby Words

radiotherapy
See all Nearby Words

Cite this Entry

“Radiotherapy.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/radiotherapy. Accessed 23 Mar. 2025.

Copy Citation

Share

Medical Definition

radiotherapy

noun
ra·​dio·​ther·​a·​py ˌrād-ē-ō-ˈther-ə-pē How to pronounce radiotherapy (audio)
plural radiotherapies
: 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

Britannica.com: Encyclopedia article about radiotherapy

Last Updated: - Updated example sentences
Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!

Popular in Grammar & Usage

See More

The Difference Between 'i.e.' and 'e.g.'

How to Use Em Dashes (—), En Dashes (–) , and Hyphens (-)

Why is '-ed' sometimes pronounced at the end of a word?

What's the difference between 'fascism' and 'socialism'?

More Commonly Misspelled Words
See More

Popular in Wordplay

See More

What do SCOTUS, POTUS, and FLOTUS mean?

Flower Etymologies For Your Spring Garden

More Words with Remarkable Origins

Terroir, Oenophile, & Magnum: Ten Words About Wine

8 Words for Lesser-Known Musical Instruments
See More

Popular Features

See More

The Difference Between 'i.e.' and 'e.g.'

What do SCOTUS, POTUS, and FLOTUS mean?

Flower Etymologies For Your Spring Garden
See More

Games & Quizzes

See All
Play Quordle: Guess all four words in a limited number of tries. Each of your guesses must be a real 5-letter word.
Quordle Can you solve 4 words at once?
Play Blossom: Solve today's spelling word game by finding as many words as you can using just 7 letters. Longer words score more points.
Blossom Word Game Pick the best words!
Play Missing Letter: a crossword with a twist. Each of the 25 puzzle words start with a different letter of the alphabet. Which letter is missing?
Missing Letter A daily crossword with a twist
dog-in-disguise
Rhyme Disguise Quiz Pair up words that look different but sound alike.
See All