oncologist
Americannoun
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
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
One medical oncologist in South Carolina, for example, took to social media to report that insurance company Humana was denying his lung cancer patient Keytruda.
From Salon • May 15, 2026
Ezekiel J. Emanuel is an oncologist, bioethicist and health-policy expert.
From MarketWatch • May 13, 2026
An advanced tumor, Ms. Khamsi says, “might harbor thousands upon thousands of mutations,” including some that may render the cancer less susceptible to whatever medication an oncologist plans to use.
From The Wall Street Journal • Apr. 20, 2026
I obviously did not get the report today that I was hoping for when my oncologist called .
From Los Angeles Times • Apr. 13, 2026
The oncologist will probably come in to ask you some questions before we start the methotrexate.
From "Drums, Girls, and Dangerous Pie" by Jordan Sonnenblick
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.
