can·cer | \ ˈkan(t)-sər \

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, 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

His son, Mike, said the cause was pancreatic cancer. New York Times, "Lindy Remigino, Olympic Champion Runner, Is Dead at 87," 12 July 2018 Taggart has saved his energy for fighting the cancer. Lori Nickel, Milwaukee Journal Sentinel, "Patient takes the fight to cancer with Scenic Shore team raising hundreds of thousands of dollars," 10 July 2018 The cancer disappeared for six months — then returned. Steve Miletich, The Seattle Times, "‘He’s just a doer’: Meet Seattle police-chief candidate Ely Reyes," 9 July 2018 Tumor was removed but transplant put on hold to make sure cancer does not return. Matthew Defranks,, "Executive let go by new Marlins ownership starts campaign to help with health costs," 9 July 2018 Being of Irish, English origin, skin cancer is a huge concern. Lindzi Scharf,, "The real reason Oscar-winner Nicole Kidman is so passionate about sunscreen," 6 July 2018 The exact treatment plan for non-Hodgkin's lymphoma depends on the type and location of the cancer but may include a combination of surgery, chemotherapy, immunotherapy, and radiation. Andrea Park, SELF, "After a Second Back Surgery, Abby Lee Miller Shows Off Her Healing Progress on Instagram," 2 July 2018 Johnson & Johnson should ready itself for a flood of new lawsuits after a jury Thursday ordered the company to pay $4.69 billion to 22 women who blamed their ovarian cancer on asbestos in its talc products, legal experts said. Jef Feeley And Margaret Cronin Fisk,, "Johnson & Johnson’s $4.69 billion talc verdict may open floodgates to more suits," 14 July 2018 Randall said doctors had caught her breast cancer in its early stages. Tegan Hanlon, Anchorage Daily News, "‘So surreal’: Olympic gold medalist Kikkan Randall announces breast cancer diagnosis, returns to Anchorage for treatment," 12 July 2018

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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Statistics for cancer

Last Updated

11 Sep 2018

Look-up Popularity

Time Traveler for cancer

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

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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

Cancer : the fourth sign of the zodiac that comes between Gemini and Leo and has a crab as its symbol


can·cer | \ ˈkan-sər \

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 \

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 \ adjective

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Comments on cancer

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the setting in which something occurs

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