ter·​a·​tol·​o·​gy | \ ˌter-ə-ˈtä-lə-jē How to pronounce teratology (audio) \

Definition of teratology

: the study of malformations or serious deviations from the normal type in developing organisms

Other Words from teratology

teratologist \ ˌter-​ə-​ˈtä-​lə-​jist How to pronounce teratologist (audio) \ noun

First Known Use of teratology

circa 1842, in the meaning defined above

History and Etymology for teratology

borrowed from French tératologie, from Greek terat-, téras "sign sent by the gods, portent, marvel, monster" + French -o- -o- + -logie -logy — more at terato-

Note: As a term in the life sciences introduced by the French zoologist Isidore Geoffroy Saint-Hilaire (1805-61) in "De la nécessité et des moyens de créer pour les Monstres une nomenclature rationelle et méthodique," Annales des sciences naturelles, tome 20 (1830), p. 326. It is uncertain if Geoffroy Saint-Hilaire was aware of the ancient Greek word teratología "account of marvelous things, marvelous tales," formed from the same elements but with an entirely different sense.

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Time Traveler for teratology

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The first known use of teratology was circa 1842

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Cite this Entry

“Teratology.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/teratology. Accessed 7 Aug. 2020.

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More Definitions for teratology


ter·​a·​tol·​o·​gy | \ ˌter-ə-ˈtäl-ə-jē How to pronounce teratology (audio) \
plural teratologies

Medical Definition of teratology

: the study of malformations or serious deviations from the normal type in organisms

More from Merriam-Webster on teratology

Britannica.com: Encyclopedia article about teratology

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