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

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Other Words from tumor

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

Examples of tumor in a Sentence

the scan showed a small tumor in her abdomen
Recent Examples on the Web This may include blood tests, imaging, and a taking a biopsy of the tumor. Texas A&m University, Chron, "PET TALK: Regular screening can help find cancer in large animals," 24 Oct. 2020 Kennedy died of a brain tumor at 77 in 2009 after serving in the U.S. Senate longer than all but three other men. Edward Kosner, WSJ, "‘Catching the Wind’ Review: The Liberal Lion in Full," 23 Oct. 2020 Murphy had surgery to remove a cancerous kidney tumor on March 5, the day New Jersey reported its first coronavirus case. Elise Young, Bloomberg.com, "Murphy’s Potential Virus Exposure Came Outdoors at Hoboken Bar," 22 Oct. 2020 In 2015, the filmmaker passed away as the result of a brain tumor. Clark Collis, EW.com, "Neve Campbell was 'apprehensive' about making Scream 5 after passing of Wes Craven," 16 Oct. 2020 One patient profiled in the piece was recommended for surgery to remove a golf-ball-size tumor in her brain but never received an appointment at all. Libby Watson, The New Republic, "Trump’s Gilded Age Coronavirus Care Is a National Shame," 6 Oct. 2020 In October, Cade will have surgery to remove the tumor and then rehab for several weeks. Dana Hunsinger Benbow, The Indianapolis Star, "Ben Davis WR Cade Thompson's message to the cancer in his leg: You're messing with the wrong kid.," 3 Oct. 2020 In July 1893, Grover Cleveland boarded a yacht to undergo secret surgery to have a tumor removed from the roof of his mouth. Maria Puente, USA TODAY, "Trump, Melania deal with COVID-19: How have past first ladies handled health crises?," 9 Oct. 2020 That knowledge did not disappear with the diagnosis of a benign tumor. Audre Lorde, Glamour, "Audre Lorde: A Black Lesbian Feminist Experience of Breast Cancer," 7 Oct. 2020

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.

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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

Time Traveler

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

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Statistics for tumor

Last Updated

28 Oct 2020

Cite this Entry

“Tumor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tumor. Accessed 28 Oct. 2020.

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More Definitions for tumor


How to pronounce tumor (audio)

English Language Learners Definition of tumor

: a mass of tissue found in or on the body that is made up of abnormal cells


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 tumour (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 tumorlike (audio) \ adjective

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