preformation

noun pre·for·ma·tion \ ˌprē-fȯr-ˈmā-shən \

Definition of preformation

1 :previous formation
2 :the now discredited theory that every germ cell contains the organism of its kind fully formed and that development involves merely an increase in size — compare epigenesis 1, homunculus 2

preformationist

play \-sh(ə-)nist\ noun or adjective

First Known Use of preformation

1732


Medical Dictionary

preformation

noun pre·for·ma·tion \ ˌprē-fȯr-ˈmā-shən \

medical Definition of preformation

:a now discredited theory in biology that every germ cell contains the organism of its kind fully formed and complete in all its parts and that development involves merely an increase in size from microscopic proportions to those of the adult — compare epigenesis

preformationist

play \-shə-nəst\ noun or adjective

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to conform or adhere

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