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

The first known use of teratology was circa 1842

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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

Comments on teratology

What made you want to look up teratology? Please tell us where you read or heard it (including the quote, if possible).


appealing forcibly to the mind or reason

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