me·​tas·​ta·​sis | \ mə-ˈta-stə-səs How to pronounce metastasis (audio) \
plural metastases\ mə-​ˈta-​stə-​ˌsēz How to pronounce metastases (audio) \

Definition of metastasis

1a : change of position, state, or form
b : the spread of a disease-producing agency (such as cancer cells) from the initial or primary site of disease to another part of the body metastasis of breast cancer to boneMedical Physics also : the process by which such spreading occurs
2 : a secondary malignant (see malignant sense 1) tumor resulting from metastasis

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Other Words from metastasis

metastatic \ ˌme-​tə-​ˈsta-​tik How to pronounce metastatic (audio) \ adjective
metastatically \ ˌme-​tə-​ˈsta-​ti-​k(ə-​)lē How to pronounce metastatically (audio) \ adverb

Examples of metastasis in a Sentence

Recent Examples on the Web Overall, the spread of cancer—referred to as metastasis—can happen through a series of steps, according to the National Cancer Institute (NCI). Maggie O'neill,, "This Man’s Colon Cancer Spread to the Surface of His Skin. Here’s How That Can Happen," 10 June 2020 That is, these tumors reinitiate an earlier developmental process to bring about invasive metastasis, dispersing the cancer and making it very hard to treat. Philip Ball, Scientific American, "Close-Up Views of Tumors Reveal a New Cancer Biology," 21 Apr. 2020 The highest level of evidence for open prostatectomy comes from randomized clinical trials showing that open surgery significantly reduces metastases and prostate-cancer deaths. WSJ, "Is Robotic Prostate Surgery Better Than Traditional Surgery?," 24 June 2018 At the Georgia Institute of Technology, for example, James E. Dahlman's laboratory is rapidly identifying safer gene therapies; others are figuring out how to combat drug resistance and prevent cancer metastasis. Scientific American, "Top 10 Emerging Technologies of 2019," 1 Dec. 2019 Pictured: a screen grab from the team's research data mapping cancer metastasis. Kieron Monks, CNN, "Unlocking the life-saving secrets of African DNA," 26 Sep. 2019 Among the three groups there was no difference in cancer recurrence, metastasis to distant parts of the body or death rates. Denise Gellene, New York Times, "Dr. Bernard Fisher, Who Revolutionized Breast Cancer Treatment, Dies at 101," 19 Oct. 2019 About 50 to 60% of individuals diagnosed with pancreatic cancer have metastasis. Joshua Bote, USA TODAY, "Rep. John Lewis and Alex Trebek have pancreatic cancer. What are symptoms, treatments?," 31 Dec. 2019 But underneath the skepticism, something else nagged at me: the sense that my incertitude was a metastasis of our jittery, gaslit world, where baseline reality is increasingly in dispute. New York Times, "The Cell, the Spell and the Mystery of ‘Sea Wall/A Life’," 27 Aug. 2019

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'metastasis.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of metastasis

1663, in the meaning defined at sense 1a

History and Etymology for metastasis

New Latin, from Late Latin, transition, from Greek, from methistanai to change, from meta- + histanai to set — more at stand

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Time Traveler for metastasis

Time Traveler

The first known use of metastasis was in 1663

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Statistics for metastasis

Last Updated

20 Jun 2020

Cite this Entry

“Metastasis.” Dictionary, Merriam-Webster, Accessed 8 Aug. 2020.

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More Definitions for metastasis


me·​tas·​ta·​sis | \ mə-ˈtas-tə-səs How to pronounce metastasis (audio) \
plural metastases\ -​ˌsēz How to pronounce metastases (audio) \

Medical Definition of metastasis

1a : change of position, state, or form
b : the spread of a disease-producing agent (as cancer cells or bacteria) or disease from the initial or primary site of disease to another part of the body The overwhelming concern about prostate cancer is its potential for metastasis—for cells to escape the gland and take root in lymph nodes, bones, lungs, skin, or other tissue.— Tom Alexander, Fortune, 20 Sept. 1993 also : the process by which such spreading occurs
2 : a secondary malignant tumor resulting from metastasis … radiation has no known effect on distant metastases from breast cancer …— David Plotkin, The Atlantic Monthly, June 1996

More from Merriam-Webster on metastasis

Britannica English: Translation of metastasis for Arabic Speakers Encyclopedia article about metastasis

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