preformation
Americannoun
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previous formation.
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Biology. (formerly) the theory that the individual, with all its parts, preexists in the germ cell and grows from microscopic to normal proportions during embryogenesis (opposed to epigenesis).
noun
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the act of forming in advance; previous formation
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biology the theory, now discredited, that an individual develops by simple enlargement of a fully differentiated egg cell Compare epigenesis
Other Word Forms
Etymology
Origin of preformation
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.
Proponents of preformation could see the evidence all around them in the natural world.
From Salon ● Jan. 17, 2016
The freshwater polyp’s ability to be split into two separate organisms did not, in his mind, fit the notion of preformation.
From Salon ● Jan. 17, 2016
Those who believed in preformation were never short of evidence.
From Salon ● Jan. 17, 2016
By the time Buffon sat down to write his own treatise of natural knowledge, the doctrine of preformation was still in vogue, even with most natural philosophers.
From Salon ● Jan. 17, 2016
The second charm of preformation was that it dispensed of the problem of de-encryption.
From "The Gene" by Siddhartha Mukherjee
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.
