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

Keep scrolling for more

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.
See More

Recent Examples on the Web

Six of the 22 plaintiffs in the latest trial have died from ovarian cancer. USA TODAY, "Nearly $4.7 billion awarded in Johnson & Johnson baby powder lawsuit," 12 July 2018 Peter was in total remission from cancer but passed due to complications of pneumonia., "Deaths in South Florida: 7/11," 11 July 2018 Janet's father passed away on June 27 from cancer, leaving his family and many people in the music community devastated. Alessandra Rincón, Billboard, "Janet Jackson Opens Up About Her Father's Death During First Performance: 'It Was Really Hard For Me'," 9 July 2018 Feelgood guitarist Wilko Johnson, who was then dying from pancreatic cancer. Dave Gil De Rubio, Detroit Free Press, "Roger Daltrey teams with DSO for Meadow Brook performance of 'Tommy'," 3 July 2018 The dog was euthanized after suffering from cancer, according to a Facebook post by a family friend. Sarah Gray, Fortune, "'Duke,' the Dog That Was the Face of Bush's Baked Beans, Has Died," 3 July 2018 The auction was an effort to raise money for children of law enforcement officers who are suffering from cancer. Michael Mcgough, sacbee, "Why 'Jurassic World' star Chris Pratt made a surprise visit to Vacaville," 25 June 2018 Ride was also in that astronaut class, but died in 2012 from cancer. Alex Stuckey, Houston Chronicle, "Three of NASA's first female astronaut recruits speaking at Space Center Houston this week," 25 June 2018 Last summer, while recovering from cancer, Lonie met with Lillian Brown of Jejusaut Ministries and asked about the family in Honduras. Ted Slowik, Daily Southtown, "Slowik: Rich Central High School helps teacher raise money to build home for family in Honduras," 22 June 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.

See More

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

Keep scrolling for more

Learn More about cancer

Statistics for cancer

Last Updated

9 Oct 2018

Look-up Popularity

Time Traveler for cancer

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

See more words from the same century

Keep scrolling for more

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

Keep scrolling for more

Comments on cancer

What made you want to look up cancer? Please tell us where you read or heard it (including the quote, if possible).


lying above or upon

Get Word of the Day daily email!

Test Your Vocabulary

Words from Greek and Roman Mythology Quiz

  • the-triumph-of-venus-by-alessandro-magnasco
  • Boreal comes from the name of the ancient Greek god of which wind?
True or False

Test your knowledge - and maybe learn something along the way.


Test Your Knowledge - and learn some interesting things along the way.


Love words? Need even more definitions?

Subscribe to America's largest dictionary and get thousands more definitions and advanced search—ad free!