preformation

[ pree-fawr-mey-shuhn ]

noun

1. previous formation.
2. 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 ( epigenesis ).

preformation

/ ˌpriːfɔːˈmeɪʃən /

noun

1. the act of forming in advance; previous formation
2. biology the theory, now discredited, that an individual develops by simple enlargement of a fully differentiated egg cell Compare epigenesis

Other Words From

• prefor·mation·ar·y adjective

Word History and Origins

Origin of preformation¹

First recorded in 1725–35; pre- + formation

Example Sentences

By the end of the seventeenth century, preformation was considered the most logical and consistent explanation for human and animal heredity.

From Literature

In France, the theory was called “embodiment”; in England, “preformation” or “preexistence.”

From Salon

The opposing views of to-day were in existence centuries ago, and they are known in the history of science as the theory of preformation or evolution, and the theory of epigenesis.

From Project Gutenberg

We mistake our power of analyzing our inner world, for its preformation, i. e. the genealogist thinks himself both originator and founder.

From Project Gutenberg

Weismann is so far right, he admits, from his materialistic premisses when he starts with preformations.

From Project Gutenberg