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noun can·cer \ˈkan(t)-sər\

Simple 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

Source: Merriam-Webster's Learner's Dictionary

Full Definition of cancer

  1. 1 capitalized a :  a northern zodiacal constellation between Gemini and Leo b (1) :  the fourth sign of the zodiac in astrology — see zodiac table (2) :  one born under the sign of Cancer

  2. 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. 3 :  something evil or malignant that spreads destructively <the cancer of hidden resentment — Irish Digest>

  4. 4 a :  an enlarged tumorlike plant growth (as that of crown gall) b :  a plant disease marked by such growths


play \ˈkan(t)s-rəs, ˈkan(t)-sə-\ adjective



Examples of cancer in a sentence

  1. He was diagnosed with cancer.

  2. She learned that she has cancer.

  3. Eating certain foods may help reduce the risk of cancer.

  4. Advanced cancers are more difficult to treat.

  5. I'm a Taurus, but my best friend is a Cancer.

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.

Origin and Etymology of cancer

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

First Known Use: 14th century

CANCER Defined for Kids


noun can·cer \ˈkan-sər\

Definition of cancer for Students

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

Medical Dictionary


noun can·cer \ˈkan(t)-sər\

Medical Definition of cancer

  1. 1:  a malignant tumor of potentially unlimited growth that expands locally by invasion and systemically by metastasis

  2. 2:  an abnormal state marked by a cancer


\ˈkan(t)s-(ə-)rəs\play adjective

Seen and Heard

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of or relating to the heavens

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