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oncology

American  
[ong-kol-uh-jee] / ɒŋˈkɒl ə dʒi /

noun

  1. the branch of medical science dealing with tumors, including the origin, development, diagnosis, and treatment of malignant neoplasms.

  2. the study of cancer.


oncology British  
/ ˌɒŋkəˈlɒdʒɪkəl, ɒŋˈkɒlədʒɪ /

noun

  1. the branch of medicine concerned with the study, classification, and treatment of tumours

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

oncology Scientific  
/ ŏn-kŏlə-jē /
  1. The branch of medicine that deals with the diagnosis and treatment of cancer.


oncology Cultural  
  1. The branch of medicine devoted to the study, treatment, and cure of cancer.


Other Word Forms

Etymology

Origin of oncology

First recorded in 1855–60; onco- + -logy

Explanation

Oncology is the branch of medicine that deals with tumors and cancer. A doctor who practices oncology is called an oncologist. You probably think of cancer treatment as a modern practice, but the word oncology has its roots in ancient Greek. The prefix onkos means "mass or bulk” (and eventually evolved into the modern Latin onco — meaning tumor) and the suffix logy means “study of.” In theory, the word means “the study of tumors.” More often, though, you will hear oncology in relation to treatment and practical medicine, as opposed to just study or research.

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Vocabulary lists containing oncology

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.

Friedmann Angeli says the importance of ferroptosis extends beyond oncology.

From Science Daily • May 15, 2026

It remains unclear if Moderna’s move into oncology will become the growth catalyst Wall Street expects, or how long that shift will take.

From Barron's • May 13, 2026

Many analysts regard it as the cornerstone of Moderna’s oncology pipeline.

From Barron's • May 8, 2026

The company said the savings would help it as it seeks to move its oncology pipeline toward commercialization.

From The Wall Street Journal • May 5, 2026

A distinction is thus drawn between cysts and growths—one which is of daily importance in the practice of medicine—and Virchow's oncology includes the consideration of the two varieties of tumors.

From A System of Practical Medicine by American Authors, Vol. I Volume 1: Pathology and General Diseases by Various

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