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 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 Varmus was inspired in part by a bladder cancer patient who responded to a generally lackluster drug because of certain mutations in her tumor. Jocelyn Kaiser, Science | AAAS, "‘Exceptional’ cancer patients yield clues to better drug treatments," 19 Nov. 2020 Jobs underwent surgery to remove his tumor in 2004 and died in 2011. Elizabeth Landau, CNN, "Why pancreatic cancer is so deadly," 8 Nov. 2020 Luckily, my tumor did shrink significantly after chemo. Glamour, "My Life In Pictures: Before, During, and After a Metastatic Breast Cancer Diagnosis," 23 Oct. 2020 King has weathered numerous health problems, including a major heart attack in 1987, the removal of a cancerous tumor in 2017, an angioplasty in 2019, and a stroke in March 2019. City News Service, Los Angeles Times, "Former talk show host Larry King is hospitalized in Los Angeles with COVID-19," 2 Jan. 2021 After her husband died of complications from a brain tumor in 2001, Margaret Lee Inloes lived alone for a few years before eventually moving into the 42-bed Gove County Medical Center Long Term Care Unit. Trevor Hughes, USA TODAY, "Deadliest place in America: They shrugged off the pandemic, then their family and friends started dying," 13 Dec. 2020 But, in fact, the term covers a wide range of hospitalizations, many of which are serious, such as removing a cancerous tumor. Sy Mukherjee, Fortune, "With hospitals increasingly full, Americans can’t get important medical treatments," 1 Dec. 2020 The death of his 46-year-old son, Beau, from a brain tumor in 2015 prevented Biden from running in 2016 as a Happy Warrior. Walter Shapiro, The New Republic, "America’s Unlikely Savior," 7 Nov. 2020 As Biden wrote in Promise Me, Dad, his 2017 book about his relationship with his son, Beau, who died from a brain tumor in 2015, the former vice president would often accompany his son to his chemotherapy treatments every other Friday. Melinda Newman, Billboard, "Bittersweet Connection Between New Radicals' Gregg Alexander & Joe Biden Leads to New Get-Out-the-Vote Ad," 2 Nov. 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

19 Feb 2021

Cite this Entry

“Tumor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tumor. Accessed 28 Feb. 2021.

Style: MLA
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More Definitions for tumor



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 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

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Comments on tumor

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