tu·​mor | \ ˈtü-mər How to pronounce tumor (audio) , ˈtyü- \

Definition of tumor

1 : an abnormal benign or malignant new growth of tissue that possesses no physiological function and arises from uncontrolled usually rapid cellular proliferation

called also neoplasm

2 : a swollen or distended part … houses that bulged with the tumors and warts of … ornamental architecture …— W. A. White

Other Words from tumor

tumoral \ ˈtü-​mə-​rəl How to pronounce tumor (audio) , ˈtyü-​ \ adjective
tumorlike \ ˈtü-​mər-​ˌlīk How to pronounce tumor (audio) , ˈtyü-​ \ adjective

Examples of tumor in a Sentence

the scan showed a small tumor in her abdomen
Recent Examples on the Web The ultrasound revealed the source of her pain: a 7-centimeter tumor filled with fluid on Boughton’s left ovary. Lauren Sausser, NBC News, 21 May 2022 More:Black women are missing from breast cancer tumor data. Nada Hassanein, USA TODAY, 19 May 2022 After migraine medications didn’t help, multiple tests were done, revealing a tumor. Shelby Dermer, The Enquirer, 17 May 2022 DeShields’s daughter, Diamond DeShields — a 6-foot-1-inch guard — won the WNBA championship as a member of the Chicago Sky last October, just 21 months after having a tumor removed from her spinal cord. Globe Staff, BostonGlobe.com, 14 May 2022 Out of that, there were around 43,000 lung cancer events and 3,700 brain tumor events. Anuradha Varanasi, Forbes, 13 May 2022 For example, if your symptoms are unusual or suddenly become severe, your doctor may order an MRI or CT scan of your brain to make sure they aren’t being caused by a tumor or bleeding in the brain. Abigail Libers, SELF, 4 May 2022 The company’s products are already helping doctors figure out if colon cancer patients still have any tumor left after treatment, whether a cancer has returned, and what treatments make most sense for those with advanced disease. Jonathan Wosen, STAT, 24 Apr. 2022 Unfortunately, vets recently caught another tumor — this one cancerous — and Spencer began chemotherapy. Caitlin O'kane, CBS News, 20 Apr. 2022 See More

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'tumor.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

First Known Use of tumor

15th century, in the meaning defined at sense 2

History and Etymology for tumor

Middle English tumour, from Latin tumor, from tumēre

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Time Traveler for tumor

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The first known use of tumor was in the 15th century

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Last Updated

26 May 2022

Cite this Entry

“Tumor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tumor. Accessed 28 May. 2022.

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More Definitions for tumor


tu·​mor | \ ˈtü-mər How to pronounce tumor (audio) , ˈtyü- \

Kids Definition of tumor

: an abnormal growth of body tissue


variants: or chiefly British tumour \ ˈt(y)ü-​mər How to pronounce tumor (audio) \

Medical Definition of tumor

: an abnormal benign or malignant new growth of tissue that possesses no physiological function and arises from uncontrolled usually rapid cellular proliferation — see cancer sense 1, carcinoma, sarcoma

Other Words from tumor

tumorlike \ -​ˌlīk How to pronounce tumor (audio) \ adjective

More from Merriam-Webster on tumor

Nglish: Translation of tumor for Spanish Speakers

Britannica English: Translation of tumor for Arabic Speakers

Britannica.com: Encyclopedia article about tumor


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