oncologist

American  

[ahng-kahl-uhj-ist] / ɑŋˈkɑl ədʒ ɪst /

noun

1. a physician who specializes in oncology.

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Explanation

An oncologist is a doctor who specializes in diagnosing and treating different forms of cancer. Hearing that a friend or family member has to visit an oncologist is never good news. Oncology is the medical treatment of cancer, and an oncologist is someone who has trained to practice oncology. Cancer is a disease that involves the abnormal growth of normal cells into masses, or tumors, and the word oncologist includes the prefix onco-, which is used in medical words to mean "tumor." It stems from the Greek root onkos, or "mass."

Example Sentences

All told, it’s still rare, at least for now, for a myeloma patient to refer to themselves as cured or for an oncologist to refer to a myeloma patient that way.

From Slate • Mar. 29, 2026

The first scene of Ann Packer’s smart, surprising novel “Some Bright Nowhere” is her final visit with the oncologist.

From The Wall Street Journal • Dec. 19, 2025

It’s also the largest known risk factor for men who get breast cancer, Hal Burstein, a breast oncologist at the Dana-Farber Cancer Institute in Boston, told MarketWatch.

From MarketWatch • Dec. 12, 2025

"These important findings identify a treatment that prolongs survival in men with aggressive prostate cancer," said Hyung Kim, MD, a urologic oncologist and chair of the Department of Urology at Cedars-Sinai.

From Science Daily • Oct. 19, 2025

To help John, she found an oncologist at Massachusetts General Hospital who would make a diagnosis without charging a fee.

From "Mountains Beyond Mountains" by Tracy Kidder and Michael French