can·​cer | \ ˈkan(t)-sər How to pronounce cancer (audio) \

Definition of cancer

1 capitalized
a : a northern zodiacal constellation between Gemini and Leo
b(1) : the fourth sign of the zodiac in astrology — see Signs of the Zodiac Table
(2) : one born under the sign of Cancer I'm a Taurus, but my best friend is a Cancer.
2 [Latin, crab, cancer]
a : a malignant tumor of potentially unlimited growth that expands locally by invasion and systemically by metastasis
b : an abnormal bodily state marked by such tumors
3 : something evil or malignant that spreads destructively the cancer of hidden resentmentIrish Digest
4a : an enlarged tumorlike plant growth (such as that of crown gall)
b : a plant disease marked by such growths

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Other Words from cancer

cancerous \ ˈkan(t)s-​rəs How to pronounce cancer (audio) , ˈkan(t)-​sə-​ \ adjective
cancerously adverb

Did You Know?

The Latin word cancer, meaning “crab,” was also given as a name to several diseases. One of the diseases was the abnormal, spreading mass of tissue we call a tumor. A possible explanation for this extended use of cancer is that the Romans thought some tumors looked like many-legged crabs. A French descendant of this Latin word was borrowed into English as canker. It is now applied to several plant and animal disorders. In the 14th century the Latin word cancer in the sense of “tumor” was borrowed directly into English, giving us our modern spelling and sense.

Examples of cancer in a Sentence

He was diagnosed with cancer. She learned that she has cancer. Eating certain foods may help reduce the risk of cancer. Advanced cancers are more difficult to treat. I'm a Taurus, but my best friend is a Cancer.
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Recent Examples on the Web Darren has been giving money to the American Cancer Society and several cancer research groups ever since her death. Sara Zeff Geber, Forbes, "Finally, Your Investments Can Reflect Your Values," 26 Feb. 2021 In his waning years, Gotti suffered from heart issues, dementia, blindness, and cancer, court documents show. Kaelan Deese, Washington Examiner, "Peter Gotti, former Gambino crime family boss, dies in prison," 26 Feb. 2021 Jamie Vigil, 39, a cancer patient who lives in Pueblo, Colo., doesn’t want to wait. Washington Post, "Vaccine lotteries and personal appeals: The medically vulnerable find their priority status slipping away," 26 Feb. 2021 The organization has created opportunities to treat and beat cancer and diabetes. Gary Curreri,, "‘Pedal for People’ charity ride returns to Boca Raton," 26 Feb. 2021 As First Lady, Dr. Biden continues her work for education, military families, and fighting cancer. Rick Green,, "First Lady Jill Biden to visit Connecticut next week," 26 Feb. 2021 The singer died of breast and spinal cancer in 2011 at age 53. Kory Grow, Rolling Stone, "Music at Home: 15 Great Punk Songs by Black Artists," 26 Feb. 2021 Calloway survived advanced breast cancer in 1975 — in the wake of a radical mastectomy, her hair not only didn’t fall out, but grew — and a more recent bacterial infection that caused gangrene. Jonathan M. Pitts,, "Still preaching at 96: Pentecostal pastor who pioneered female leadership inspires in Baltimore and beyond," 26 Feb. 2021 Clinics provided treatments for cold and flu symptoms, especially for kids, and a range of preventative care, such as physicals, immunizations, gynecological exams, dental exams and cancer screenings. Arpita Aneja, Time, "With Free Medical Clinics and Patient Advocacy, the Black Panthers Created a Legacy in Community Health That Still Exists Amid COVID-19," 25 Feb. 2021

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'cancer.' 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 cancer

14th century, in the meaning defined at sense 1a

History and Etymology for cancer

Middle English, from Latin (genitive Cancri), literally, crab; akin to Greek karkinos crab, cancer

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Time Traveler for cancer

Time Traveler

The first known use of cancer was in the 14th century

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Statistics for cancer

Last Updated

1 Mar 2021

Cite this Entry

“Cancer.” Dictionary, Merriam-Webster, Accessed 6 Mar. 2021.

Style: MLA
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More Definitions for cancer



English Language Learners Definition of cancer

: a serious disease caused by cells that are not normal and that can spread to one or many parts of the body
: something bad or dangerous that causes other bad things to happen
: the fourth sign of the zodiac that comes between Gemini and Leo and has a crab as its symbol


can·​cer | \ ˈkan-sər How to pronounce cancer (audio) \

Kids Definition of cancer

: a serious sometimes deadly disease characterized by the growth of abnormal cells that form tumors which may damage or destroy normal body tissue


can·​cer | \ ˈkan(t)-sər How to pronounce cancer (audio) \

Medical Definition of cancer

1 : a malignant tumor of potentially unlimited growth that expands locally by invasion and systemically by metastasis
2 : an abnormal state marked by a cancer

Other Words from cancer

cancerous \ ˈkan(t)s-​(ə-​)rəs How to pronounce cancer (audio) \ adjective

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