PREFORMATION

preformation, theory of preformation

(noun) a theory (popular in the 18th century and now discredited) that an individual develops by simple enlargement of a tiny fully formed organism (a homunculus) that exists in the germ cell

Source: WordNet® 3.1

Etymology

Noun

preformation (countable and uncountable, plural preformations)

Prior formation.

(biology, historical) The theory that organisms are fully developed in the form of an egg or seed, and just increase in size (as opposed to epigenesis).

Source: Wiktionary

Pre`for*ma"tion, n. (Biol.)

Definition: An old theory of the preëxistence of germs. Cf. Emboîtement.

Source: Webster’s Unabridged Dictionary 1913 Edition