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 cancerous (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 The group confirmed that the initial mutations often cropped up years or decades before the cancers were diagnosed, suggesting many could be detected and treated much earlier. Jocelyn Kaiser, Science | AAAS, "Massive cancer genome study reveals how DNA errors drive tumor growth," 5 Feb. 2020 The recommendations, published last month, embrace positions held by public health authorities and experts for plaintiffs who allege that contaminated talc products caused their cancers. NBC News, "FDA to hold public meeting on testing for asbestos in talc," 4 Feb. 2020 These powerful pollutants can contribute to respiratory illnesses, mental health conditions, and cancer, and have been tied to many other conditions. Ula Chrobak, Popular Science, "Decades of U.S. air quality improvements may be slowing, and these areas have it the worst," 4 Feb. 2020 The additional deaths were from causes linked to unhealthy behaviour, including heart disease, lung cancer, liver disease and drug poisoning. The Economist, "Daily chart Starting work in a recession affects people for their whole lives," 4 Feb. 2020 Her son David Diamond said the cause was metastatic breast cancer. Anita Gates, New York Times, "Hester Diamond, Passionate Art Collector, Is Dead at 91," 31 Jan. 2020 Hodgkin's Lymphoma is a cancer of the immune system, according to the Mayo Clinic. Sarah Ladd, The Courier-Journal, "He beat cancer. Now, this Louisville teen is going to the Super Bowl with Make-a-Wish," 27 Jan. 2020 People who are obese face heightened risk for diabetes, heart disease, stroke, high blood pressure and certain types of cancers, among other conditions. Dana Goldman, The Conversation, "Obesity, second to smoking as the most preventable cause of US deaths, needs new approaches," 27 Jan. 2020 The study showed a link between 14 different PFAS chemicals and cancer, birth defects, thyroid disease, and liver damage. National Geographic, "Toxic ‘forever chemicals’ more common in tap water than thought, report says," 24 Jan. 2020

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

13 Feb 2020

Cite this Entry

“Cancer.” Dictionary, Merriam-Webster, Accessed 24 Feb. 2020.

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More Definitions for cancer


How to pronounce cancer (audio)

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 cancerous (audio) \ adjective

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More from Merriam-Webster on cancer

Rhyming Dictionary: Words that rhyme with cancer

Spanish Central: Translation of cancer

Nglish: Translation of cancer for Spanish Speakers

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

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