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

Such exposure may raise the risk of asthma and cancer, as well as derail the normal development of a child’s body and brain., "Son nagged by golfing dad’s death from a rare cancer; were pesticides at fault?," 15 June 2019 In December 2013, Brian was diagnosed with throat cancer, and during his treatment, asked Jordan not to visit him in hospital. Ben Morse, CNN, "Father's Day: Unforgettable dad moments in sport," 15 June 2019 Diagnosed with stage 4 cervical cancer, doctors have given her six months to live. Deanese Williams-harris,, "Two years after burying her mother, Chalise Scholl is relying on social media to pay for her own funeral," 14 June 2019 Bear bile, however, is also marketed as a cure for cancer, colds, hangovers, and more, though there is no scientific evidence supporting its effectiveness for these ailments. National Geographic, "Bear bile, explained," 12 June 2019 The study also underscores the lack of research linking IF with improvements in health outcomes, such as memory loss, diabetes, heart disease, cancer, and stroke. Samantha Cassetty, NBC News, "Is the Dubrow Diet healthy? A dietitian weighs in," 12 June 2019 To contribute funds for others fighting rare cancers, chip in to the #ChipInChallenge here. Hadley Keller, House Beautiful, "Gabe Grunewald, Pro Runner and Friend of Chip and Joanna Gaines, Has Died," 12 June 2019 Some conditions allowed in Ohio are covered in other states, including cancer, Parkinson’s disease, epilepsy and glaucoma. Anne Saker,, "Medical marijuana: Ohio board votes today on whether autism, anxiety will be qualifying conditions," 11 June 2019 Social isolation affects cardiovascular health, mental health and even has implications for cancer risk, according to Julianne Holt-Lunstad, a researcher studying social isolation. Spencer Morgan, New York Times, "Youths! Go Listen to Your Elders!," 8 June 2019

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

19 Jun 2019

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
: 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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