[ tuh-rat-uh-juhn, -jen, ter-uh-tuh- ]

  1. a drug or other substance capable of interfering with the development of a fetus, causing birth defects.

Origin of teratogen

First recorded in 1900–05; terato- + -gen

Other words from teratogen

  • te·rat·o·gen·ic, adjective

Words Nearby teratogen

Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2023

British Dictionary definitions for teratogen


/ (ˈtɛrətədʒən, tɪˈrætə-) /

  1. any substance, organism, or process that causes malformations in a fetus. Teratogens include certain drugs (such as thalidomide), infections (such as German measles), and ionizing radiation

Derived forms of teratogen

  • teratogenic, adjective
  • teratogenicist, noun
  • teratogenicity, noun

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

Scientific definitions for teratogen


[ tə-rătə-jən, tĕrə-tə- ]

  1. An agent, such as a virus, a drug, or radiation, that can cause malformations in an embryo or fetus.

The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.