cancer

noun

can·​cer ˈkan(t)-sər How to pronounce cancer (audio)
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
4
a
: an enlarged tumorlike plant growth (such as that of crown gall)
b
: a plant disease marked by such growths
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
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Late Mom 'Happy Heavenly Birthday' 9 Months After Her Death from Cancer In February 2024, Dever announced in an Instagram post that her mother, Kathy, died after a 14-year battle with metastatic breast cancer. Esther Kang, People.com, 12 May 2025 At this time, the cancer is termed castration-resistant prostate cancer (CRPC). Matthew Wosnitzer, Verywell Health, 12 May 2025 Some studies show that eating watermelon could lower the risk of cancer, heart disease, diabetes, and other health problems.32 A Quick Review Fruits like apples, peaches, guava, and mangoes are highly nutritious. Lindsey Desoto, Health, 12 May 2025 The decision came after over a dozen residents bemoaned the practice at a public meeting, blaming fluoride for bone deficiencies, cancer and Alzheimer’s disease. Angela Palermo, Idaho Statesman, 12 May 2025 See All Example Sentences for cancer

Word History

Etymology

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

First Known Use

14th century, in the meaning defined at sense 1a

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

Browse Nearby Words

Cite this Entry

“Cancer.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/cancer. Accessed 19 May. 2025.

Kids Definition

cancer

noun
can·​cer ˈkan(t)-sər How to pronounce cancer (audio)
1
capitalized : a group of stars between Gemini and Leo usually pictured as a crab
2
capitalized
a
: the fourth sign of the zodiac see zodiac
b
: a person whose sign of the zodiac is Cancer
3
: a tumor that tends to spread locally and to other parts of the body and often causes death if not treated
also : an abnormal state marked by such tumors
4
: a dangerous evil that destroys slowly
cancerous adjective
Etymology

Middle English Cancer "'Crab' star group," from Latin cancer "crab, cancer (disease)"; sense 3 directly from Latin cancer "crab, cancer" — related to canker, chancre

Word Origin
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.

Medical Definition

cancer

noun
can·​cer ˈkan(t)-sər How to pronounce cancer (audio)
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
cancerous adjective

More from Merriam-Webster on cancer

Last Updated: - Updated example sentences
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