tumor

play

noun tu·mor \ˈtü-mər, 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

tumoral

play \-mə-rəl\ adjective

tumorlike

play \-mər-ˌlīk\ adjective

See tumor defined for English-language learners

See tumor defined for kids

Examples of tumor in a Sentence

the scan showed a small tumor in her abdomen

Recent Examples of tumor from the Web

McCain underwent a minor procedure last week to remove a blood clot from above his left eye, which lab results later revealed was associated with a brain tumor known as a glioblastoma.

— aria bendix, The Atlantic, "John McCain Diagnosed With Brain Cancer," 19 July 2017
Senator John McCain has been diagnosed with a brain tumor, his office said Wednesday.

— margaret hartmann, Daily Intelligencer, "John McCain Diagnosed With Brain Cancer," 19 July 2017
Christine’s husband had insurance that allowed her to undergo radiation treatment in Casablanca after her tumor was successfully removed by surgery in Senegal in November.

— carley petesch, The Seattle Times, "In West Africa, cancer patients forced abroad for treatment," 14 July 2017
For girls, pyometra (uterine infections) and mammary tumors are the biggest risk.

— patty khuly, miamiherald, "Spay or neuter your dog? Vet says you don’t have to but you should," 13 July 2017
Which is part of the reason Warner felt comfortable sharing video of her open brain surgery, which removed 95% of the tumor.

— lilian min, Cosmopolitan, "Beauty Vlogger Courtney Elizabeth Warner Shared a Video of Her Open Brain Surgery," 11 July 2017
Cindy was looking her over and looking for all the signs that this is Mo — a stitch in her right eye, her fatty tumor.

— nicole blanchard, idahostatesman, "This dog spent 9 months lost in the Idaho mountains. Here’s how she got home to Boise," 8 July 2017
Doctors found two tumors, one stretching across Audrey's chest and down her torso, Cox said.

— emma kate fittes, Indianapolis Star, "Audrey Lupton dies as friends rallied to help complete bucket list," 5 July 2017
Only two studies could be reproduced; one result was negative, and two studies were ruled inconclusive because of problems with mouse tumor models.

— jocelyn kaiser, Science | AAAS, "Cancer studies pass reproducibility test," 27 June 2017

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.

Origin and Etymology of tumor

Middle English tumour, from Latin tumor, from tumēre

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First Known Use: 15th century

See Words from the same year

Other Medicine Terms

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TUMOR Defined for English Language Learners

tumor

play

noun

Definition of tumor for English Language Learners

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

TUMOR Defined for Kids

tumor

play

noun tu·mor \ˈtü-mər, ˈtyü-\

Definition of tumor for Students

: an abnormal growth of body tissue

Medical Dictionary

tumor

noun tu·mor

variants: or chiefly British

tumour

\ˈt(y)ü-mər\play

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 1, carcinoma, sarcoma