tumor

noun

tu·​mor ˈtü-mər How to pronounce tumor (audio)
ˈtyü-
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 adjective
tumorlike adjective

Examples of tumor in a Sentence

the scan showed a small tumor in her abdomen
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
The increase was found in certain types of cancer including leukemias, lymphomas, brain tumors, hepatic tumors, and gonadal germ cell tumors, according to the study. Mary Kekatos, ABC News, 5 Mar. 2025 Mia Love, the first Black Republican woman elected to Congress, is no longer responding to treatment for an aggressive and malignant brain tumor known as glioblastoma, with which she was diagnosed in 2022. Cara Lynn Shultz, People.com, 3 Mar. 2025 That kind of tumor originates in nervous system cells, according to the Cleveland Clinic, and the grade Mixsooke had was aggressive, base officials said. Sara Schilling, Sacramento Bee, 3 Mar. 2025 This is an alternative treatment option for depression, anxiety, OCD, PTSD and other mental health conditions, along with migraines, brain tumors, epilepsy and chronic pain. Mari Pressley, Charlotte Observer, 3 Mar. 2025 See All Example Sentences for tumor

Word History

Etymology

Middle English tumour, from Latin tumor, from tumēre

First Known Use

15th century, in the meaning defined at sense 2

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

Browse Nearby Words

Cite this Entry

“Tumor.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tumor. Accessed 9 Mar. 2025.

Kids Definition

tumor

noun
tu·​mor ˈt(y)ü-mər How to pronounce tumor (audio)
: an abnormal mass of tissue that arises from normal tissue cells and serves no useful purpose in the body
tumorous
ˈt(y)üm-(ə-)rəs
adjective

Medical Definition

tumor

noun
tu·​mor
variants or chiefly British tumour
: 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
tumorlike adjective

More from Merriam-Webster on tumor

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