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Synonyms

carcinogen

American  
[kahr-sin-uh-juhn, -jen, kahr-suh-nuh-jen, -noh-] / kɑrˈsɪn ə dʒən, -ˌdʒɛn, ˈkɑr sə nəˌdʒɛn, -noʊ- /

noun

Pathology.

  1. any substance or agent that tends to produce a cancer.

carcinogen British  
/ ˈkɑːsɪnəˌdʒɛn, kɑːˈsɪnədʒən /

noun

  1. pathol any substance that produces cancer

"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
carcinogen Scientific  
/ kär-sĭn′ə-jən /

  1. A substance or agent that can cause cells to become cancerous by altering their genetic structure so that they multiply continuously and become malignant. Asbestos, DDT, and tobacco smoke are examples of carcinogens.

Other Word Forms

  • anticarcinogen noun
  • anticarcinogenic adjective
  • carcinogenic adjective
  • carcinogenicity noun

Etymology

Origin of carcinogen

First recorded in 1935–40; carcino- + -gen

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.

Its active ingredient is glyphosate, which the International Agency for Research on Cancer, a unit of the World Health Organization, identified in 2015 as a probable human carcinogen.

From BBC • Feb. 17, 2026

The International Agency for Research on Cancer considers glyphosate, one of Roundup's ingredients, a probable human carcinogen, but Bayer says scientific studies and regulatory approvals show the weedkiller is safe.

From Barron's • Feb. 17, 2026

Some studies have found it is a likely carcinogen, and others concluded it does not pose a true cancer risk for humans.

From Los Angeles Times • Jan. 16, 2026

Antimony, which can trigger gastrointestinal problems, and chromium, a known carcinogen, were present above acceptable levels in 24.3% and 20% of the toys, respectively.

From Science Daily • Nov. 28, 2025

The story of the trout is important for many reasons, but chiefly as an example of what can happen when a potent carcinogen is introduced into the enviroment of any species.

From "Silent Spring" by Rachel Carson

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.