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

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.
Recent Examples on the Web The race is a repeat of a battle between the two candidates waged last year to replace the seat’s previous holder, Sonna Singleton Gregory, who died after a battle with cancer in May 2021. Leon Stafford, ajc, 9 May 2022 The blood drive was organized again by family members in honor of the late Kimberley Benedyk Sandford, 49, a Naperville mom who died on March 3, 2020, following an eight-year battle with cancer. David Sharos, Chicago Tribune, 8 May 2022 Last year my mother passed away after a 15-year battle with lung cancer. Abigail Van Buren, oregonlive, 8 May 2022 Kathy Boudin, the teacher, organizer, and revolutionary, died on May 1st, after a seven-year battle with cancer. Rachael Bedard, The New Yorker, 7 May 2022 The prolific penciler’s death Friday was confirmed in a statement on his Facebook page, noting that complications stemming from his lengthy battle with pancreatic cancer as the cause of death. Daniel Kreps, Rolling Stone, 7 May 2022 He was diagnosed with pancreatic cancer on Nov. 27, 2021. Abbey White, The Hollywood Reporter, 7 May 2022 Last December, Pérez announced that he was diagnosed with pancreatic cancer. Wilson Chapman, Variety, 7 May 2022 Unfortunately, Tony has once again been diagnosed with cancer. Elise Brisco, USA TODAY, 6 May 2022 See More

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.

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

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

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Last Updated

12 May 2022

Cite this Entry

“Cancer.” Dictionary, Merriam-Webster, Accessed 21 May. 2022.

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More Definitions for cancer


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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