preformation

American  

[pree-fawr-mey-shuhn] / ˌpri fɔrˈmeɪ ʃən /

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 ).

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preformation British  

/ 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

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Other Word Forms

• preformationary adjective

Etymology

Origin of preformation

First recorded in 1725–35; pre- + formation

Example Sentences

The peculiar charm of this idea—called preformation—was that it was infinitely recursive.

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

A step towards the mechanical solution of this problem was indicated in the “preformation theory” advanced by Leibnitz, and elaborated by Bonnet.

From Project Gutenberg