metastasis

noun

me·​tas·​ta·​sis mə-ˈta-stə-səs How to pronounce metastasis (audio)
plural metastases mə-ˈta-stə-ˌsēz How to pronounce metastasis (audio)
1
a
: 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
metastatic adjective
metastatically adverb

Examples of metastasis 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.
Medical professionals usually use a detailed system called TNM – short for tumor, nodes, metastasis – to classify a tumor’s stage. Jason P. Joseph, The Conversation, 21 May 2025 This is the general explanation for why about 10 percent of patients newly diagnosed with prostate cancer are found to have metastasis (typically bone or lymph nodes) at the time of initial diagnosis. Khaleda Rahman, MSNBC Newsweek, 20 May 2025 This places the cancer in Grade Group 5, the highest risk category, associated with a greater likelihood of metastasis and a more challenging prognosis. Eric M. Strauss, ABC News, 18 May 2025 Tumor resection, including limb amputation, is the usual first-line treatment, while chemotherapy is given in combination with surgery to improve survival time by reducing the risk of metastasis. Paul McClure 26, New Atlas, 26 May 2025 See All Example Sentences for metastasis

Word History

Etymology

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

First Known Use

1663, in the meaning defined at sense 1a

Time Traveler
The first known use of metastasis was in 1663

Browse Nearby Words

Cite this Entry

“Metastasis.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/metastasis. Accessed 11 Jun. 2025.

Kids Definition

metastasis

noun
me·​tas·​ta·​sis mə-ˈtas-tə-səs How to pronounce metastasis (audio)
plural metastases -ˌsēz How to pronounce metastasis (audio)
1
: the spread of something that produces disease (as cancer cells) from the original location of disease to another part of the body
2
: a growth of a malignant tumor in another part of the body resulting from metastasis

Medical Definition

metastasis

noun
me·​tas·​ta·​sis mə-ˈtas-tə-səs How to pronounce metastasis (audio)
plural metastases -ˌsēz How to pronounce metastasis (audio)
1
a
: 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
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

More from Merriam-Webster on metastasis

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